Arylation of ortho-Hydroxyarylenaminones by Sulfonium Salts and Arenesulfonyl Chlorides: An Access to Isoflavones

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Arylation of ortho-Hydroxyarylenaminones by Sulfonium Salts and

Arenesulfonyl Chlorides: An Access to Isoﬂavones

Satenik Mkrtchyan* and Viktor O. Iaroshenko*

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ABSTRACT: Herein we disclose three new methods for the straightforward and eﬃcient synthesis of 3-arylchromones following

the arylation of ortho-hydroxyarylenaminones by vast diversities of bench-stable and easy-to-use sulfonium salts and arenesulfonyl

chlorides. Both developed methods, namely the light-mediated photoredox and electrophilic arylation, showed good eﬃciency, and

are feasible for the preparation of 3-arylchromones in good-to-excellent yields. This work showcases the ﬁrst described attempt

where the sulfonium salts and arenesulfonyl chlorides were successfully utilized for the construction of the chromone heterocycle

system.

includes the C−C couplings between 3-halogen-chromones

with arylboronic acids,²arylstanyls, triarylbismuths,³as well as

arylzincbromide reagents⁴used as coupling counterparts, while

decarboxylative Suzuki−Miyaura coupling of (hetero)aromatic

carboxylic acids was also utilized;⁵palladium-catalyzed oxidative

cross-coupling reaction of arylboronic acids with 3-diazo-2,3-

dihydro-4H-1-benzopyran-4-one is another way to reach 3-

arylchromones.⁶(ii) The second disconnection is based upon

the arylation of ortho-hydroxyarylenaminones which leads via

domino cyclization to the construction of the chromone core.

Among these are direct arylation of ortho-hydroxyarylenami-

nones following either visible-light-mediated protocol using

aryldiazonium and diaryliodonium salts,⁷or oxidative C−H

activation route utilizing arylboronic acids⁸along with Pd-

catalysis. (iii) Construction of 3-arylchromones can also be

achieved by [4 + 2] cyclization reactions of salicylaldehyde with

the set of 1,2-CC-building blocks.⁹At the same time, other

INTRODUCTION

■

It is rather diﬃcult to overestimate the importance and the role

of isoﬂavones, a class of naturally occurring compounds which

are often referred to in the contemporary literature as 3-

arylchromones. Besides application in various aspects of human

life, these compounds have gained a pivotal position in medicine

and life science.¹The application of 3-arylchromones and their

functionalized derivatives as a part of herbal extracts can be

traced back to ancient times. In addition, nowadays, the 3-

arylchromone scaﬀold is a well-known pharmacophore of

utmost importance with a broad spectrum of biological

properties, among which one should highlight the following

activities: antimicrobial, antiestrogenic, cardiovascular, anti-

inﬂammatory, chemopreventative activities, and antioxidant

action.¹

The importance of this heterocyclic system and its broad

application justiﬁes the development of more eﬃcient and low-

cost preparative methods as well as strategies for late-stage

diversiﬁcation of chromones and 3-arylchromones. Presently

known synthetic routes for construction of 3-arylchromone

framework by their virtue can be divided into six main tactics

(Figure 1), namely the following: (i) The installation of aryl

substituents at the position 3 of the chromone skeleton is very

often bolstered on the set of well-developed C−C-couplings

using 3-functionalized chromones as a starting point. This

Received: September 26, 2020

Published: March 15, 2021

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Figure 1. Synthetic tactics for construction of isoﬂavone framework.

strategies like (iv) [3 + 3]-cyclizations,¹⁰(v) [5 + 1]-

cyclizations,¹¹and (vi) intermolecular cyclizations of appro-

priate linear precursors¹²constitute a vast set of reaction used for

preparation of the title heterocycles. On the other hand, more

obsolete strategies which have no practical applications

nowadays were also utilized.^13,14Many of the presented tactics

are tedious multistep routes which involve cumbersome

procedures, in some cases with poor functional group tolerance

and insuﬃcient eﬃciency. Thus, there is a growing need of new

synthetic tactics which can address the current challenges in

concise preparation of 3-arylchromones. A recent tendency in

contemporary organic chemistry literally implies search for new,

green, low-cost, and more eﬃcient methods which would allow

for generation of vast diversities of privileged complex organic

molecules. The preparation of 3-substituted chromones is very

often based upon the functionalization of ortho-hydroxyaryle-

naminones featuring either electrophilic¹⁵or radical reagents.¹⁶

The latest tactics involving carbon-centered radicals are still at a

nascent stage of development and scarcely presented in the

modern literature by seven examples only.^7,17,18

Owing to the great potential the light-mediated synthetic

strategies have, very recently we expanded the pool of known

concise methodologies for 3-arylchromone preparation by two

methods, which are based upon the arylation of ortho-

hydroxyarylenaminones by aryl diazonium and diaryliodonium

salts catalyzed by Eosin Y and Ru(bpy)₃Cl₂, respectively.⁷Both

synthetic methodologies exerted high yields and excellent

functional group tolerance. As we continue our quest for new

strategies aimed at an eﬃcient preparation of chromones,^7,16,19

and in a view of our recently developed methods which utilize

aryldiazonium tetraﬂuoroborates and the diaryliodonium

hexaﬂuorophosphates,⁷we considered other onium salts,

namely the sulfonium salts, which are often described as

synthetic equivalents of aryl halides in photoredox and transition

metal-catalyzed cross-coupling reactions, as reagents ﬁt for the

application for the highlighted arylation scenario. Given the

recent literature data on the chemical properties and behavior of

sulfonium reagents, we also assumed that the aryl sulfonium

moiety can undergo photocatalytic reduction by numerous

photoredox catalysts enabling the generation of the elusive aryl

radical intermediates.²⁰

On the other hand, dialkyl aryl sulfonium salts showed

propensity to react with numerous soft and hard nucleophiles,

thus being used as eﬃcient arylation agents in reaction with

various heteroatom nucleophiles, providing a facile route for N−

C, O−C, B−C, S−C, Se−C, Si−C, and Sn−C bond

formation.²¹Recent studies show that mechanistically these

reactions represent a classical aromatic nucleophilic substitution

(S_NAr). Moreover, sulfonyl chlorides are widely used precursor

for photo generation of aryl radicals using transition-metal and

organic dye photocatalysts; further, these processes were

coupled with numerous arylation scenarios.^20e,22Thus, taking

into account at least two diﬀerent reaction mechanisms known

for the reactivity of aryl sulfonium salts and the propensity of

sulfonyl chlorides to be utilized as precursors for generation of

aryl radicals, we set three synthetic scenarios, meant for aryl

functionalization of ortho-hydroxyarylenaminones based on (a)

the direct transition-metal free electrophilic arylation and (b, c)

photoredox arylation protocols, respectively (Schemes 1, 2). In

turn, we presumed that these transformations might have to

proceed via the formation of the intermediates A and B,

respectively (Scheme 1).

RESULTS AND DISCUSSION

■

Initial studies were aimed at the design of eﬃcient reaction

conditions for the three title model reactions. First, we assumed

that for the direct arylation of ortho-hydroxyarylenaminones

optimal reagent, due to the sterical encumbrance caused by

bulkier Ar₂S residue, should be the dimethyl(aryl)sulfoniums

and the reaction should take place in polar aprotic solvents in the

presence of a base. This was the starting point in the reaction

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switched our attention to the more readily available ruthenium

photocatalysts III−V. It is of note that all three catalytic species

were prone to promote the title model reaction and enabled the

formation of chromone derivative 5e in diﬀerent yields (Table

S2, Entries 11−16, 20, 21). After changing such variables like

solvent, base, and the reaction duration, we came onto the

formulation of the optimal reaction conditions, which we further

used for deployment of this synthetic protocol, preceding the

range of experiments where we used diﬀerent Ru-based

photocatalysts from Scheme 2 and tested numerous solvents

and additives (for more details see Table S2). Finally, after

optimization the chromone 5e was prepared in 92% yield

utilizing the nonsophisticated reaction conditions by using

sulfonium salt 3d (1.4 equiv), photocatalyst Ru(bpy)₃Cl₂·6H₂O

(2 mol %), NaOAc (1.8 equiv), reaction took place in CH₃CN,

reached completions within 3 h at room temperature under

intensive blue LED irradiation (Table S2, Entry 14). Notably, to

prove that this synthetic scenario takes a radical arylation

pathway, we conducted a classical TEMPO quenching experi-

ment under the best reaction conditions, which completely

suppressed the radical domino cyclization and did not yield the

expected chromone product (Table S2, Entry 17). The reactions

conducted in the dark without photocatalysts also experienced a

failure (Table S2, Entries 18, 19). Despite the fact that the best

reaction conditions were successfully identiﬁed, we screened the

photocatalysts VI−VIII, which showed lower eﬃciency to our

great disappointment (Table S2, Entries 22−27).

Having in hand optimized reaction conditions for all two

synthetic scenarios, next we focused on the evaluation of the

scope and limitations of these newly developed protocols. For

the synthesis of 3-arylchromones by electrophilic arylation of

ortho-hydroxyarylenaminones we selected 13 dimethyl(aryl)-

sulfonium salts 2 with TfO⁻, BF₄⁻and MeSO₃⁻contra anions

and reacted them with eight ortho-hydroxyarylenaminones. This

resulted in the synthesis of 28 title chromone representatives in

good-to-excellent yields (Scheme 3a). This protocol was

competent with a variety of electron-deﬁcient and electron-

rich substituents on both coupling substrates; even the

dimethyl(aryl)sulfoniums bearing substituents in the ortho

position showed good outcomes (Scheme 3, Compounds 5d,

5u, 5w, 5y, 5aa). This synthetic method not only demonstrated

broad functional group tolerance, but also is scalable on 10 and

20 mmol quantities.

Scheme 1. Mechanism-Based Reactivity of Aryl Sulfonium

Salts and Aryl Sulfonyl Chloride with ortho-

Hydroxyarylenaminones

conditions optimization for the model reaction of the Scheme 2a

between the corresponding ortho-hydroxyarylenaminone 1b and

the (4-ﬂuorophenyl)dimethylsulfonium triﬂuoromethanesulfo-

nate 2i illustrated in the Table S1 in the Supporting Information.

Thus, the best outcome was observed when we took DMF as a

solvent and Cs₂CO₃as a base; these conditions allowed for the

preparation of the model compound 5e in 89% yield (Table S1,

Entries 8−12). Other variations, for instance K₂CO₃as a base

(Entries 4, 5, 7, 13) and solvents such as CH₃CN and DMSO

(Entries 1−6), appeared to be less operational and delivered the

desired product in lower yields. Overall, we formulated the best

reaction conditions which consisted of using of Cs₂CO₃as a base

and dry DMF as a solvent. It requires 1.3 excess of

dimethyl(aryl)sulfonium salt; with this composition the reaction

reached its completion within 5 h at 90 °C (Table S1, Entry 9).

Noteworthy, relatively low reduction potential of sulfonium

salts conditions the use of stronger reductants for the

photoredox-promoted generation of free aryl radicals. In

particular, the iridium and ruthenium complexes such as fac-

Ir(ppy)₃I, Ir[dF(CF₃)ppy]₂(dtbbpy)PF₆II and Ru(bpy)₃Cl₂·

6H₂O III are often used for the photoreductive generation of

aryl radicals via a reductive cleavage of C−S bound in sulfonium

salts.²³We commenced by testing the complexes I−III as

potential photocatalysts to the model reaction depicted in the

Scheme 2b, where we aimed to exploit the reactivity of the

dimethyl(aryl)sulfoniums 2 under the photoredox conditions.

Unfortunately, the initial screening of reaction conditions

showcased that salts 2 were actually prone to reacting with the

ortho-hydroxyarylenaminone generating the expected chro-

mones, albeit with low eﬃciencythe best hit within the Ir

catalyst II based conditions yielded the chromone molecule in

47% yield (not mentioned in the Supporting Information).

Thus, as the second option, corresponding triarylsulfonium salts

3 were put into consideration. To our great delight ﬁrst setups

with these salts using iridium complexes I and II in combination

with either sodium carbonate or acetate led to the successful

formation of the compound 5e (Table S2, Entries 1−10). The

best reaction conditions for iridium photocatalysts I and II were

the utilization of 1.5 equiv of sulfonium salt, NaOAc (1.8 equiv)

as a base with DMSO as solvent; in both cases the corresponding

chromone was isolated in 84% and 89% yield, respectively

(Entries 6, 10). We witnessed that the elimination of the base

resulted in a drastic drop of the yields of the model compound 5e

for these two reactions (Table S2, Entries 7, 8). Next, we

Next, we focused on the evaluation of the practical utility of

photocatalytic arylation protocol (Scheme 3b): following, the

scope was demonstrated on the instance of eight ortho-

hydroxyarylenaminones and ten triarylsulfoniums possessing

−

TfO⁻, PF₆, CI⁻, Br⁻as contra anions, thus allowing for the

preparation of 21 3-arylchromones 5. This methodology

demonstrated the same profound degree of tolerance for the

diverse substitution patterns. Some discrepancy in yields was

observed only for the aryl sulfoniums bearing ortho substituents,

for instance, for compounds 5d, 5w, 5aa; this might be

addressed by considering the sterical impact of the correspond-

ing aryl substituents. The two protocols described above possess

potent synthetic leeway limited only by the accessibility of the

corresponding sulfonium reagents.

After successfully developing the optimal reaction conditions

for two above presented protocols utilizing sulfonium salts and

accurately studying the scope of these methods, next we shifted

our focus to the exploration of the reaction between ortho-

hydroxyarylenaminones and sulfonyl chlorides (Scheme 2c).

Here we probed diverse reaction conditions employing the

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Scheme 2. Model Reactions and Photocatalysts for Reaction Conditions Optimization

photocatalysts I−VI and VIII. We foreknew that ortho-

hydroxyarylenaminones might not react eﬃciently with the

sulfonyl chlorides due to the presence of the free OH function,

and the OH group can quench the sulfonyl chloride, thus

hampering the reaction overall. Indeed, this hypothesis was

supported by a range of experiments with poor performance

(Table S3, Entries 1−13). Namely, the best outcome overall for

all used transition metal catalysts was observed in the case of Ir

photocatalyst II under intensive blue light irradiation enabling

the synthesis of the title chromone 5a in 44% yield (Table S3,

Entry 6). Furthermore, organic dye Eosin Y, with blue LED

irradiation source, exerted promising catalytic capacity (Table

S3, Entries 9−13), under these conditions the formation of the

model chromone was observed in 28% yield (Table S3, Entry

11).

In contrary, the OH-protected enaminone substrates 6, in

particularly OMe derivative 6a, were prone to undergo

eﬃciently the radical triggered domino arylation catalyzed by

numerous transition-metal photocatalysts. As a result, within the

frames of these studies we developed several optimal reaction

conditions which allowed for the eﬀective preparation of the

model chromone compound 5a (Table S3, Entries 14−17, 21−

25, 32, 33). Namely, iridium complexes I and II as well as

ruthenium complexes III, IV, and V showed suﬃcient catalytic

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Scheme 3. Product Scope of 3-Arylchromones Using Sulfonium Salts

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Scheme 4. Product Scope of 3-Arylchromones Using Sulfonyl Chlorides

activity toward the title model reaction. We also ascertained that

both, the solvent and the base, make a profound impact on the

eﬃciency of this synthetic protocol. In particular, optimized

reaction condition for the catalyst II by using the combination of

arenesulfonyl chloride (2.2 equiv), Ir[dF(CF₃)ppy]₂(dtbbpy)-

PF₆(1 mol %), Na₂CO₃(2 equiv), conducting reaction in

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Scheme 5. Proposed Reaction Mechanisms for the Synthesis of 3-Arylchromones

CH₃CN for 12 h enabled the preparation of the model

chromone compound in 83%. At the same time the best

reaction conditions were prone to transform the OEt, OCH₂Ph,

and OPh containing ortho-hydroxyarylenaminones 6b, 6c, and

6d into the corresponding chromone 5a obtained in 80%, 85%,

and 68% yields respectively (Table S3, Entries 18−20).

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Finally, ruthenium bipyridyl complex III, which due to its low

price was often preferred by us over iridium 2-phenylpyrdine

complexes as a suitable photocatalyst of choice, was successfully

introduced into this study (Table S3, Entries 21−25). As a

result, the optimized reaction conditions employed the use of

arenesulfonyl chloride (1.8 equiv), Ru(bpy)₃Cl₂(2 mol %),

Na₂CO₃(2 equiv), reaction conducted in CH₃CN were

developed allowing for the preparation of the model 3-

arylchromone in 90% yield (Table S3, Entry 25). Moreover,

we studied the role of R substituent for the Ru-based reaction

conditions: not only the Me-group-containing ortho-hydroxyar-

ylenaminones 6a, but also derivatives furnished with other

functionalities like Et, CH₂Ph, Ph, and allyl were tested within

the frames of this synthetic protocol. It appeared that (a) The

presence of Me, Et, and CH₂Ph substituents enables the facile

chromone ring formation, and all these functionalities are

eﬃcient leaving groups within the current protocol; (b) On the

other hand, the Ph group, placed onto the OH, had also

showcased visible propensity to be cleaved within this synthetic

protocol leading to the formation of the title chromone, albeit in

lower yield (Table S3, Entries 26−29). In the case of allyl

derivative, the reaction did not experience a failure delivering the

model compound in 10% yield.

Unexpectedly and to our great delight the optimized reaction

conditions can also be transferred onto the ortho-hydroxyar-

ylenaminones 1a, thus synthesis of chromone 5a was achieved in

42% yield when the reaction was run 4 h, increasing the reaction

time to 10 h enabled synthesis of corresponding compound in

57% yield (Table S3, Entries 30, 31). The substitution of the

2,2′-bipyridine ligand versus 2,2′-bipyrimidine (Photocatalyst

IV) and versus 2,2′-bipyrazine (Photocatalyst V) caused an

inferior eﬃciency (Table S3, Entries 32, 33). Notably, the Cu-

based complexes VI and VII were not prone at all to catalyze the

title transformation (Table S3, Entries 34−37).

With these results in hand and aiming at elaborating more

eﬃcient and low-cost methodologies, we decided to use readily

available Ru(bpy)₃Cl₂·6H₂O III instead of high-priced Ir-based

photocatalysts I and II. Following, the optimized reaction

conditions for further deployment of this synthetic protocol

were employed as follows: sulfonium salt (1.8 equiv), Ru-

(bpy)₃Cl₂(2 mol %), Na₂CO₃(2 equiv), as solvent CH₃CN was

used, reaction was conducted under Ar atmosphere, at room

temperature. Our observation shows that the maximum

duration of reaction to be completed was 4 h (Table S3, Entry

25). Noteworthy, in order to ﬁnd an evidence that the described

radical-triggered domino cyclization involves the formation of

the aryl radicals, several control experiments were performed for

the arylation of enaminones 1a, 6a, 6c by arenesulfonyl chloride,

such as addition of TEMPO (2 equiv) under the optimal

reaction conditions as well as reactions conducted with no light

irradiation and without photocatalyst experienced failure (Table

S3, Entries 38−46).

To the scope for arylation of the O-substituted ortho-

hydroxyarylenaminones 6: here ten corresponding enaminone

precursors 6 and 20 sulfonyl chlorides 4 were reacted, and this

led to the preparation of the chromone library of 25 compounds.

Noteworthy, this protocol demonstrated high tolerance toward

multiple functional groups, with two synthetic scenarios

discussed earlier, it even was eﬃcient in case of ortho-substituted

sulfonyl chlorides (Scheme 4). For instance, compounds 5ac,

5ag, and 5ao were prepared in 73%, 71% and 65% yields,

respectively. Here we also compared the eﬃciency of two

arylation protocols, namely the one starting from the ortho-

hydroxyarylenaminones 1 with the one which utilizes corre-

sponding O-alkylated derivatives 6 (Scheme 4, the yields for the

case using ortho-hydroxyarylenaminones 1 are highlighted in

green).

To further demonstrate the synthetic utility of these two

protocols, the gram-scale reactions were performed using 10 and

20 mmol of corresponding ortho-hydroxyarylenaminones and

O-alkylated derivatives, which successfully yielded the corre-

sponding chromones with negligible discrepancy in yields

(Scheme 3, 4).

On the basis of the described vide supra results and the

presently known literature on the chemical properties of

sulfonium salts, their reactions with nucleophiles via an S_NAr

pathway,^21a,24and light-mediated photoredox radical arylation

reactions, we postulated plausible reaction mechanisms which

are presented schematically in the Scheme 5. The arylation of

ortho-hydroxyarylenaminones by dimethyl(aryl)sulfonium salts

perhaps commences with the initial electrophilic attack

following the S_NAr nucleophilic substitution, which undergoes

via the corresponding transition state followed by the mentioned

vide supra intermediary cation structure 7 (Scheme 5).

Subsequently, the latest in turn cyclizes to form 2-

(dimethylamino)chromanone 8 which then, after elimination

of dimethylamine, gives rise to the ﬁnal 3-arylchromone 5.

Noteworthy, in order to deliver an evidence that the arylation

reaction does not proceed via radical mechanism, we conducted

an experiment with the widely used radical scavengerthe

TEMPO; this resulted in the slight decrease of the yield to 81%

(Entry 14). We repeated this experiment several times and

always observed insigniﬁcant yields depression. This result can

be accepted as indisputable evidence, which allows us to rule out

the involvement of radical intermediates.

Regarding the visible-light photocatalyzed synthesis of 3-

arylchromones 5 by using triarylsulfonium and arenesulfonyl

chlorides catalyzed by Ru(bpy)₃Cl₂·6H₂O III, the pathways

commence by a SET oxidation of the excited photocatalyst in

triplet state leading to the C−S bond fragmentation and

subsequent generation of the reactive aryl radical (Ar·); the

latest in turn then attacks the enaminone moiety to aﬀord the

carbon-centered radical intermediate 9. This type of radical

intermediate species was previously described in several visible-

light driven syntheses of chromones, in particular 3-thiocyanato,

3-polyﬂuoroalkyl, and 3-aryl chromones.^7,17,18The latest

undergoes prompt oxidation to carbocation 10, which

subsequently follows the sequence described in the Scheme 5a

to yield the target chromone 5.

Summing up, for the ﬁrst time sulfonium salts and

arenesulfonyl chlorides were successfully utilized for the direct

C−H functionalization of ortho-hydroxyarylenaminones and

corresponding O-substituted derivatives. Three novel strategies

which enable an eﬃcient and concise access to vast diversities of

3-arylchromones, build upon the electrophilic arylation using

dimethyl(aryl)sulfonium salts, and upon photoredox arylation

by triarylsulfonium and arenesulfonyl chlorides, respectively,

with Ru(bpy)₃Cl₂·6H₂O as a photocatalyst, were ascertained

within this study. The scope of the developed tactics is

thoroughly studied and covers vast substitution patterns on

both the chromone and the aryl parts. We also compared these

three methodologies in terms of their eﬃciencies and scalability.

Noteworthy, the large structural diversities of arenesulfonyl

chlorides available commercially, even despite the required

prefunctionalization of ortho-hydroxyarylenaminones, high-

lights the overall value of this synthetic protocol. The

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the dry CH₃CN (0.12 mmol/mL) was added and the reaction vial was

properly capped by Teﬂon Mininert Valve. Finally, the reaction vial was

removed from the glovebox and subjected to irradiation under vigorous

stirring using 34 W blue LED lamps (Kessil KSH150B Blue LED Grow

Light; 5−6 cm away, with cooling fan on top to keep the reaction

mixture at room temperature) for 3 h. The reaction was controlled by

both GC MS and TLC. After completion the reaction mixture was

evaporated until dryness using rotary evaporator, the content of the

ﬂask was generously treated with distilled water, ﬁltrated, and ﬁnally

properly dried in a vacuum. The resulting crude was directly subjected

to gradient ﬂash chromatography on silica gel using appropriate mixture

of hexane/ethyl acetate as eluent to isolate the desired chromone

derivative.

mechanistic studies revealed the involvement of free-radical

pathways in the case of visible-light-mediated photoredox

arylation routes.

EXPERIMENTAL SECTION

■

Commercially available starting materials, reagents, catalysts, anhy-

drous and degassed solvents were used without further puriﬁcation.

Flash column chromatography was performed with Merck Silica gel 60

(230−400 mesh). The solvents for column chromatography were

distilled before use. Thin layer chromatography was carried out using

Merck TLC Silica gel 60 F₂₅₄and visualized by short-wavelength

ultraviolet light or by treatment with potassium permanganate

1

(KMnO₄) stain. H, ¹³C, and ¹⁹F NMR spectra were recorded on a

The gram scale synthesis was performed on 10 and 20 mmol of the

starting ortho-hydroxyarylenaminone.

Bruker 250 and 500 MHz at 20 °C. All ¹H NMR spectra are reported in

parts per million (ppm) downﬁeld of TMS and were measured relative

General Procedure for the Synthesis of 3-Arylchromones 5

by the Reaction of ortho-Hydroxyarylenaminones 1 with

Triarylsulfonium Salts 3 Using Ir Catalyst. Under inert atmosphere

(glovebox operating with a constant Ar-purge) to a 20 mL vial equipped

with a stir bar was placed photocatalyst Ir[dF(CF₃)ppy]₂(dtbbpy)PF₆

(11 mg, 0.01 mmol, 0.01 equiv), NaOAc (148 mg, 1.8 mmol, 1.8 equiv)

appropriate ortho-hydroxyarylenaminone (1.0 mmol, 1.0 equiv) and

appropriate triarylsulfonium salt (1.5 mmol, 1.5 equiv); then the dry

DMSO (0.2 mmol/mL) was added and the reaction vial was properly

capped by Teﬂon Mininert Valve. Finally, the reaction vial was removed

from the glovebox and subjected to irradiation under vigorous stirring

using 34 W blue LED lamps (Kessil KSH150B Blue LED Grow Light;

5−6 cm away, with cooling fan on top to keep the reaction mixture at

room temperature) for 4 h. The reaction was controlled by both GC MS

and TLC. After completion the reaction mixture was evaporated until

dryness using rotary evaporator, the content of the ﬂask was generously

treated with distilled water, ﬁltrated, and ﬁnally properly dried in a

vacuum. The resulting crude was directly subjected to gradient ﬂash

chromatography on silica gel using appropriate mixture of hexane/ethyl

acetate as eluent to isolate the desired chromone derivative.

General Procedure for the Synthesis of 3-Arylchromones 5

by the Reaction of O-Alkylated ortho-Hydroxyarylenaminones

6 and ortho-Hydroxyarylenaminones 1 with Arenesulfonyl

Chlorides 4 Using Ru Catalyst. Under inert atmosphere (glovebox

operating with a constant Ar-purge) to an 25 mL vial equipped with a

stir bar was placed photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02

mmol, 0.02 equiv), Na₂CO₃(212 mg, 2 mmol, 2 equiv) appropriate O-

alkylated ortho-hydroxyarylenaminone or ortho-hydroxyarylenaminone

(1.0 mmol, 1.0 equiv) and appropriate arenesulfonyl chloride (1.8

mmol, 1.8 equiv); then the dry CH₃CN (0.10 mmol/mL) was added

and the reaction vial was properly capped by Teﬂon Mininert Valve.

Finally, the reaction vial was removed from the glovebox and subjected

to irradiation under vigorous stirring using 34 W blue LED lamps

(Kessil KSH150B Blue LED Grow Light; 5−6 cm away, with cooling

fan on top to keep the reaction mixture at room temperature) for 4 h.

The reaction was controlled by both GC MS and TLC. After

completion the reaction mixture was evaporated until dryness using

rotary evaporator, the content of the ﬂask was generously treated with

distilled water, ﬁltrated, and ﬁnally properly dried in a vacuum. The

resulting crude was directly subjected to gradient ﬂash chromatography

on silica gel using appropriate mixture of hexane/ethyl acetate as eluent

to isolate the desired chromone derivative.

to the signals for CHCl₃(7.26 ppm) and DMSO (2.50 ppm). All ¹³

C

NMR spectra were reported in ppm relative to residual CHCl₃(77.00

ppm) or DMSO (39.70 ppm) and were obtained with ¹H decoupling.

Coupling constants, J, are reported in Hertz (Hz). Gas chromato-

graphic analyses was performed on a gas chromatograph mass

spectrometer GCMS-QP2010 Ultra instrument.

The optimal reaction conditions were identiﬁed by microscale high-

throughput experimentation screening. Parallel synthesis was accom-

plished in an MBraun glovebox operating with a constant Ar-purge

(oxygen and water <5 ppm). As a light source a standard commercially

available Kessil KSH150B Blue LED Grow Light was used. Screening

reactions were carried out in 10 mL vials using suitable heating blocks.

Liquid chemicals were dosed using gastight microsyringes. Isolation of

obtained compounds was achieved by column chromatography on

Silica gel.

All used reagents 1, 2, 3, 4, and 6 are literature known compounds

and were prepared according to the known literature; the spectral data

is identical with the corresponding literature sources. Namely, ortho-

hydroxyarylenaminones 1,²⁵which we used several times in our

previous research, corresponding O-substituted derivatives 6,²⁶and

sulfonium salts 2²⁷and 3²⁸are literature described substances. All

arenesulfonyl chlorides 4 used here are commercially available and were

purchased from appropriate vendors.

General Procedure for the Synthesis of 3-Arylchromones 5

by the Reaction of ortho-Hydroxyarylenaminones 1 with

Dimethyl(aryl)sulfonium Salts 2. Under inert atmosphere (glove-

box operating with a constant Ar-purge) to an 10 mL ﬂask equipped

with a stir bar was placed appropriate ortho-hydroxyarylenaminone (1.0

mmol, 1.0 equiv), appropriate dimethyl(aryl)sulfonium salt (1.3 mmol,

1.3 equiv), and Cs₂CO₃(487 mg, 1.5 mmol, 1.5 equiv), then the

reaction vial was properly capped by rubber septum. Finally, the

reaction vessel was removed from the glovebox, connected to a pressure

compensator (balloon partially ﬁlled with Argon equipped with a

needle), and installed on the stirring plate equipped with an ice bath;

subsequently the dry DMF (0.3 mmol/mL) was added using a syringe

and the reaction mixture left by at 0 °C for 30 min. Subsequently, the

reaction mixture was kept 1 h at room temperate and then subjected to

heating at 90 °C for 5 h. The reaction was controlled by both GC MS

and TLC. After completion the reaction mixture was evaporated until

dryness using rotary evaporator, the crude was generously treated with

distilled water, dried once more, and afterward was directly subjected to

gradient ﬂash chromatography on silica gel using appropriate mixture of

hexane/ethyl acetate as eluent to isolate the desired chromone

derivative.

The gram scale synthesis was performed on 10 and 20 mmol of the

starting ortho-hydroxyarylenaminone.

3-(3-(Triﬂuoromethyl)phenyl)-4H-chromen-4-one (5a). The

title compound was prepared starting from ortho-hydroxyarylenami-

none 1a (191 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)-

sulfonium salt 2e (463 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg,

1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5a (255 mg, 0.88 mmol, 88%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6a (205 mg, 1.0 mmol, 1.0 equiv) and

The gram scale synthesis was performed on 10 and 20 mmol of the

starting ortho-hydroxyarylenaminone.

General Procedure for the Synthesis of 3-Arylchromones 5

by the Reaction of ortho-Hydroxyarylenaminones 1 with

Triarylsulfonium Salts 3 Using Ru Catalyst. Under inert

atmosphere (glovebox operating with a constant Ar-purge) to a 20

mL vial equipped with a stir bar was placed photocatalyst Ru(bpy)₃Cl₂·

6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv), NaOAc (148 mg, 1.8 mmol,

1.8 equiv) appropriate ortho-hydroxyarylenaminone (1.0 mmol, 1.0

equiv) and appropriate triarylsulfonium salt (1.4 mmol, 1.4 equiv); then

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appropriate arenesulfonyl chloride 4h (440 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5a (261 mg, 0.90 mmol, 90%). The gram scale synthesis was

performed on 10 and 20 mmol of the starting O-alkylated ortho-

hydroxyarylenaminone and desired 5a was prepared in 82% (2.38 g, 8.2

mmol) and 77% (4.47 g, 15.4 mmol) yields, respectively.

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1a (191 mg, 1.0 mmol, 1.0 equiv), and appropriate

arenesulfonyl chloride 4h (440 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5a (165 mg, 0.57 mmol, 57%). The gram scale synthesis was performed

on 10 mmol of the starting ortho-hydroxyarylenaminone and desired 5a

was prepared in 46% (1.33 g, 4.6 mmol) yield.

6-Methyl-3-(p-tolyl)-4H-chromen-4-one (5c). The title com-

pound was prepared starting from ortho-hydroxyarylenaminone 1b

(205 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)sulfonium

salt 2b (393 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg, 1.5 mmol,

1.5 equiv) and the dry DMF (0.3 mmol/mL). The puriﬁcation of the

dry crude performed by column chromatography on silica gel provides

the desired chromone 5c (225 mg, 0.90 mmol, 90%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3b (636 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5c (218 mg, 0.87 mmol, 87%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv), and appropriate

arenesulfonyl chloride 4b (343 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5c (150 mg, 0.60 mmol, 60%).

In all previous cases gradient ﬂash column chromatography was

performed using a mixture of hexane/ethyl acetate 7:1 to 5:1 as eluent

to provide corresponding chromone. R_f= 0.7 (Hex:EtAc 3:1).

White solid, mp 138−139 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.11

(s, 1H), 7.99 (s, 1H), 7.47−7.51 (m, 3H), 7.36 (d, 1H, ³J = 8.1 Hz),

7.26 (d, 2H, ³J = 7.3 Hz), 2.48 (s, 3H), 2.41 (s, 3H). ¹³C{¹H} NMR

(126 MHz, CDCl₃) δ 176.4, 154.5, 152.7, 137.9, 135.1, 134.8, 129.2,

129.0, 128.8, 125.6, 125.1, 124.2, 117.7, 21.2, 21.0. MS (GC, 70 eV) m/

z (%) = 250 (M⁺, 100), 134 (32), 115 (24). Anal. Calcd for C₁₇H₁₄O₂:

C, 81.58; H, 5.64. Found: C, 81.62; H, 5.70.

6-Methyl-3-(o-tolyl)-4H-chromen-4-one (5d). The title com-

pound was prepared starting from ortho-hydroxyarylenaminone 1b

(205 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)sulfonium

salt 2c (393 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg, 1.5 mmol,

1.5 equiv) and the dry DMF (0.3 mmol/mL). The puriﬁcation of the

dry crude performed by column chromatography on silica gel provides

the desired chromone 5d (152 mg, 0.61 mmol, 61%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3c (636 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5d (185 mg, 0.74 mmol, 74%).

Alternatively the title compound was prepared starting from

Ir[dF(CF₃)ppy]₂(dtbbpy)PF₆(11 mg, 0.01 mmol, 0.01 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv), and appropriate

triarylsulfonium salt 3c (681 mg, 1.5 mmol, 1.5 equiv) and dry DMSO

(0.2 mmol/mL). The puriﬁcation of the dry crude performed by

column chromatography on silica gel provides the desired chromone 5d

(188 mg, 0.75 mmol, 75%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv), and appropriate

arenesulfonyl chloride 4m (483 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5d (77 mg, 0.31 mmol, 31%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 8:1 as eluent to provide

corresponding chromone. R_f= 0.3 (Hex:EtAc 5:1).

White solid, mp 97−98 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.31 (dd,

1H, ³J = 7.9 Hz, ⁴J = 1.6 Hz), 8.07 (s, 1H), 7.84 (s, 1H), 7.78 (d, 1H, ³J =

7.8 Hz), 7.70−7.73 (m, 1H), 7.64 (d, 1H, ³J = 7.9 Hz), 7.56 (t, 1H, ³J =

7.7 Hz), 7.51 (d, 1H, ³J = 8.5 Hz), 7.46 (t, 1H, ³J = 7.9 Hz). ¹³C{¹H}

NMR (126 MHz, CDCl₃) δ 175.9, 156.2, 153.4, 134.0, 132.6, 131.0 (q,

²J_CF= 33.0 Hz), 128.9, 126.3, 125.6 (m), 125.5, 124.9 (m), 124.3 (d, J_CF

= 23.5 Hz), 124.0 (q, ¹J_CF= 272.6 Hz), 118.1. HRMS (TOF MS ES+)

m/z [M + H]⁺calcd for C₁₆H₁₀O₂F₃291.0640, found 291.0633.

3-(4-Chlorophenyl)-4H-chromen-4-one (5b). The title com-

pound was prepared starting from ortho-hydroxyarylenaminone 1a

(191 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)sulfonium

salt 2j (419 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg, 1.5 mmol,

1.5 equiv) and the dry DMF (0.3 mmol/mL). The puriﬁcation of the

dry crude performed by column chromatography on silica gel provides

the desired chromone 5b (190 mg, 0.84 mmol, 84%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1a (191 mg, 1.0 mmol, 1.0 equiv), and appropriate

triarylsulfonium salt 3e (722 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5b (213 mg, 0.83 mmol, 83%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6a (205 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4o (381 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5b (203 mg, 0.79 mmol, 79%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1a (191 mg, 1.0 mmol, 1.0 equiv), and appropriate

arenesulfonyl chloride 4o (381 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5b (133 mg, 0.50 mmol, 50%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 10:1 as eluent to provide

corresponding chromone. R_f= 0.5 (Hex:EtAc 6:1).

White solid, mp 186−187 °C. ¹H NMR (500 MHz, CDCl₃) δ 7.40−

7.46 (m, 3H), 7.48−7.52 (m, 3H), 7.68−7.72 (m, 1H), 8.02 (s, 1H),

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 8:1 as eluent to provide

corresponding chromone. R_f= 0.6 (Hex:EtAc 3:1).

3

4

8.30 (dd, 1H, J = 8.0 Hz, J = 1.6 Hz). ¹³C{¹H} NMR (126 MHz,

CDCl₃) δ 176.0, 156.2, 153.0, 134.2, 133.8, 130.3, 130.2, 128.7, 126.4,

125.4, 124.4, 124.3, 118.1. MS (GC, 70 eV) m/z (%) = 256 (M⁺, 100),

136 (16), 120 (66), 110 (16), 92 (65). Anal. Calcd for C₁₅H₉ClO₂: C,

70.19; H, 3.53. Found: C, 70.23; H, 3.49.

Light brown solid, mp 221−222 °C. ¹H NMR (500 MHz, CDCl₃) δ

8.05 (br. s, 1H), 7.82 (s, 1H), 7.45 (dd, 1H, ³J = 8.7 Hz, ⁴J = 1.8 Hz),

7.35 (d, 1H, ³J = 8.7 Hz), 7.25−7.28 (m, 2H), 7.20−7.21 (m, 1H), 7.14

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(d, 1H, ³J = 7.3 Hz), 2.43 (s, 3H), 2.22 (s, 3H). ¹³C{¹H} NMR (126

MHz, CDCl₃) δ 176.0, 154.6, 153.4, 135.1, 138.0, 134.8, 131.7, 130.4,

130.1, 128.5, 126.2, 125.7, 125.6, 123.9, 117.8, 20.9, 20.0. MS (GC, 70

eV) m/z (%) = 250 (M⁺, 49), 135 (100), 115 (32), 77 (20). Anal. Calcd

for C₁₇H₁₄O₂: C, 81.58; H, 5.64. Found: C, 81.53; H, 5.73.

3-(4-Fluorophenyl)-6-methyl-4H-chromen-4-one (5e). The

title compound was prepared starting from ortho-hydroxyarylenami-

none 1b (205 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)-

sulfonium salt 2i (398 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg,

1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5e (226 mg, 0.89 mmol, 89%).

The gram scale synthesis was performed on 10 and 20 mmol of the

starting ortho-hydroxyarylenaminone and desired 5e was prepared in

83% (2.11 g, 8.3 mmol) and 79% (4.01 g, 15.8 mmol) yields,

respectively.

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3d (652 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5e (233 mg, 0.92 mmol, 92%). The gram scale synthesis was performed

on 10 and 20 mmol of the starting ortho-hydroxyarylenaminone and

desired 5e was prepared in 86% (2.18 g, 8.6 mmol) and 73% (3.76 g,

14.8 mmol) yields, respectively.

Alternatively the title compound was prepared starting from

Ir[dF(CF₃)ppy]₂(dtbbpy)PF₆(11 mg, 0.01 mmol, 0.01 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv), and appropriate

triarylsulfonium salt 3d (699 mg, 1.5 mmol, 1.5 equiv) and dry DMSO

(0.2 mmol/mL). The puriﬁcation of the dry crude performed by

column chromatography on silica gel provides the desired chromone 5e

(229 mg, 0.90 mmol, 90%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv), and appropriate

arenesulfonyl chloride 4n (350 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5e (147 mg, 0.58 mmol, 58%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 12:1 as eluent to provide

corresponding chromone. R_f= 0.5 (Hex:EtAc 5:1).

Light brown solid, mp 208−209 °C. ¹H NMR (500 MHz, CDCl₃) δ

8.08 (br. s, 1H), 8.00 (s, 1H), 7.50−7.53 (m, 3H), 7.42 (s, 1H), 7.38−

7.41 (m, 2H), 2.48 (s, 3H). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ due to

bad solubility it was not possible to measure. HRMS (TOF MS ES+)

m/z [M + H]⁺calcd for C₁₆H₁₂O₂Cl 271.0529, found 271.0526.

3-(4-Methoxyphenyl)-6-methyl-4H-chromen-4-one (5g).

The title compound was prepared starting from ortho-hydroxyarylena-

minone 1b (205 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl-

(aryl)sulfonium salt 2h (330 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃

(487 mg, 1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5g (205 mg, 0.77 mmol, 77%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3f (703 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5g (229 mg, 0.86 mmol, 86%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv), and appropriate

arenesulfonyl chloride 4e (440 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5g (141 mg, 0.53 mmol, 53%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 5:1 as eluent to provide

corresponding chromone. R_f= 0.5 (Hex:EtAc 3:1).

Yellow solid, mp 119−120 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.09

(br. s, 1H), 7.97 (s, 1H), 7.48 (dd, 1H, ³J = 8.5 Hz, ⁴J = 2.1 Hz), 7.30−

7.33 (m, 2H), 7.36 (d, 1H, ³J = 8.5 Hz), 6.97 (dd, 2H, ³J = 8.7 Hz, ⁴J =

1.9 Hz), 3.48 (s, 3H), 2.47 (s, 3H). ¹³C{¹H} NMR (126 MHz, CDCl₃)

δ 176.5, 159.5, 154.4, 152.4, 135.0, 134.8, 130.1, 125.6, 124.7, 124.3,

124.1, 117.7, 114.0, 55.3, 21.0. HRMS (TOF MS ES+) m/z [M + H]⁺

calcd for C₁₇H₁₅O₃267.1033, found 267.1021.

6-Methyl-3-phenyl-4H-chromen-4-one (5h). The title com-

pound was prepared starting from ortho-hydroxyarylenaminone 1b

(205 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)sulfonium

salt 2a (374 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg, 1.5 mmol,

1.5 equiv) and the dry DMF (0.3 mmol/mL). The puriﬁcation of the

dry crude performed by column chromatography on silica gel provides

the desired chromone 5h (205 mg, 0.87 mmol, 87%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3a (577 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5h (193 mg, 0.82 mmol, 82%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv), and appropriate

arenesulfonyl chloride 4a (318 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5h (130 mg, 0.55 mmol, 55%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 10:1 as eluent to provide

corresponding chromone. R_f= 0.6 (Hex:EtAc 5:1).

White solid, mp 202−203 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.08

(br. s, 1H), 7.99 (s, 1H), 7.53−7.56 (m, 2H), 7.50 (dd, 1H, ³J = 8.5 Hz,

⁴J = 2.0 Hz), 7.38 (d, 1H, ³J = 9.1 Hz), 7.13 (t, 2H, ³J = 8.8 Hz), 2.48 (s,

3H). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ 176.2, 162.7 (d, ¹J_CF= 242.0

Hz),21.0, 154.5, 152.8, 135.3, 135.0, 130.6 (d, J_CF= 8.1 Hz), 127.9,

125.6, 124.2 (d, J_CF= 22.9 Hz), 117.8, 115.4 (d, J_CF= 21.6 Hz). HRMS

(TOF MS ES+) m/z [M + H]⁺calcd for C₁₆H₁₂O₂F 255.0831, found

255.0821.

3-(4-Chlorophenyl)-6-methyl-4H-chromen-4-one (5f). The

title compound was prepared starting from ortho-hydroxyarylenami-

none 1b (205 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)-

sulfonium salt 2j (419 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg,

1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5f (238 mg, 0.88 mmol, 88%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3e (722 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5f (246 mg, 0.91 mmol, 91%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 7:1−5:1 as eluent to provide

corresponding chromone. R_f= 0.6 (Hex:EtAc 3:1).

Yellow solid, mp 104−105 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.09

(br s, 1H), 7.99 (s, 1H), 7.56−7.58 (m, 2H, CH_Ar), 7.43−7.49 (m, 3H),

7.36−7.40 (m, 2H), 2.46 (s, 3H). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ

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176.1, 20.9, 154.4, 152.9, 135.1, 117.7, 134.8, 131.9, 128.8, 128.4, 128.1,

125.6, 125.0, 124.1. HRMS (TOF MS ES+) m/z [M + H]⁺calcd for

C₁₆H₁₃O₂237.0925, found 237.0916.

(126 MHz, CDCl₃) δ 175.2, 164.3, 158.0, 153.0, 135.7, 130.1 (q, ²J_CF

=

31.8 Hz), 129.2, 127.8, 123.3 (m), 124.2, 124.2 (q, ¹J_CF= 273.3 Hz),

118.3, 114.9, 55.9. HRMS (TOF MS ES+) m/z [M + H]⁺calcd for

C₁₇H₁₂O₃F₃321.0744, found 321.0739.

3-(4-(tert-Butyl)phenyl)-6-methyl-4H-chromen-4-one (5i).

The title compound was prepared starting from ortho-hydroxyarylena-

minone 1b (205 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl-

(aryl)sulfonium salt 2m (447 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃

(487 mg, 1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5i (236 mg, 0.81 mmol, 81%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3h (715 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5i (248 mg, 0.85 mmol, 85%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1b (205 mg, 1.0 mmol, 1.0 equiv), and appropriate

arenesulfonyl chloride 4r (419 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5i (166 mg, 0.57 mmol, 57%).

7-Methoxy-3-(p-tolyl)-4H-chromen-4-one (5k). The title com-

pound was prepared starting from ortho-hydroxyarylenaminone 1c

(221 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)sulfonium

salt 2b (393 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg, 1.5 mmol,

1.5 equiv) and the dry DMF (0.3 mmol/mL). The puriﬁcation of the

dry crude performed by column chromatography on silica gel provides

the desired chromone 5k (226 mg, 0.85 mmol, 85%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1c (221 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3g (862 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5k (234 mg, 0.88 mmol, 88%).

In all previous cases gradient ﬂash column chromatography was

performed using a mixture of hexane/ethyl acetate 5:1 to 1:1 as eluent

to provide corresponding chromone. R_f= 0.45 (Hex:EtAc 3:1).

Light yellow solid, mp 135−136 °C. ¹H NMR (500 MHz, CDCl₃) δ

8.20 (d, 1H, ³J = 9.0 Hz), 7.92 (s, 1H), 7.44 (d, 2H, ³J = 8.6 Hz), 7.23

(d, 2H, ³J = 8.3 Hz), 6.98 (dd, 1H, ³J = 8.8 Hz, ⁴J = 2.2 Hz), 6.83 (d, 1H,

⁴J = 2.4 Hz), 3.90 (s, 3H), 2.39 (s, 3H). ¹³C{¹H} NMR (126 MHz,

CDCl₃) δ 175.7, 164.0, 157.9, 152.3, 137.9, 129.1, 128.9, 128.8, 127.7,

125.1, 118.4, 114.5, 100.0, 55.7, 21.2. HRMS (TOF MS ES+) m/z [M +

H]⁺calcd for C₁₇H₁₅O₃267.1024, found 267.1021.

6-Fluoro-3-(4-ﬂuorophenyl)-4H-chromen-4-one (5l). The title

compound was prepared starting from ortho-hydroxyarylenaminone 1c

(221 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)sulfonium

salt 2i (398 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg, 1.5 mmol,

1.5 equiv) and the dry DMF (0.3 mmol/mL). The puriﬁcation of the

dry crude performed by column chromatography on silica gel provides

the desired chromone 5l (206 mg, 0.80 mmol, 80%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 5:1−3:1 as eluent to provide

corresponding chromone. R_f= 0.7 (Hex:EtAc 3:1).

Light yellow solid, mp 133−134 °C. ¹H NMR (500 MHz, CDCl₃) δ

8.11 (br s, 1H), 8.00 (s, 1H), 7.52−7.53 (m, 2H), 7.47−7.48 (m, 3H),

7.37 (d, 1H, ³J = 9.1 Hz), 2.47 (s, 3H), 1.37 (s, 9H, tBu). ¹³C{¹H} NMR

(126 MHz, CDCl₃) δ 176.3, 154.4, 152.8, 151.0, 135.0, 134.7, 129.0,

128.5, 125.6, 125.4, 124.9, 124.1, 117.7, 34.6, 31.2, 20.9. MS (GC, 70

eV) m/z (%) = 292 (M⁺, 38), 277 (100), 115 (13). Anal. Calcd for

C₂₀H₂₀O₂: C, 82.16; H, 6.90. Found: C, 82.23; H, 6.83.

7-Methoxy-3-(4-(triﬂuoromethyl)phenyl)-4H-chromen-4-

one (5j). The title compound was prepared starting from ortho-

hydroxyarylenaminone 1c (221 mg, 1.0 mmol, 1.0 equiv), appropriate

dimethyl(aryl)sulfonium salt 2f (462 mg, 1.3 mmol, 1.3 equiv), and

Cs₂CO₃(487 mg, 1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/

mL). The puriﬁcation of the dry crude performed by column

chromatography on silica gel provides the desired chromone 5j (288

mg, 0.90 mmol, 90%). The gram scale synthesis was performed on 10

mmol of the starting ortho-hydroxyarylenaminone and desired 5k was

prepared in 91% (2.56 g, 8.0 mmol) yield.

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1c (221 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3g (862 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5j (291 mg, 0.91 mmol, 91%). The gram scale synthesis was performed

on 10 mmol of the starting ortho-hydroxyarylenaminone and desired 5j

was prepared in 74% (2.37 g, 7.4 mmol) yield.

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6f (235 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4d (440 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5j (282 mg, 0.88 mmol, 88%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1c (221 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3d (862 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5l (230 mg, 0.89 mmol, 89%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6g (223 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4n (350 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5l (217 mg, 0.84 mmol, 84%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1d (209 mg, 1.0 mmol, 1.0 equiv), and appropriate

arenesulfonyl chloride 4n (350 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5l (142 mg, 0.50 mmol, 55%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 5:1−1:1 as eluent to provide

corresponding chromone. R_f= 0.4 (Hex:EtAc 3:1).

White solid, mp 190−191 °C. ¹H NMR (500 MHz, CDCl₃): 8.70 (s,

1H), 7.82−7.89 (m, 1H), 7.77 (dt, 1H, ³J = 8.9 Hz, ⁴J = 3.0 Hz), 7.47−

7.53 (m, 3H), 7.23−7.27 (m, 1H). ¹³C{¹H} NMR (126 MHz, CDCl₃):

Due to bed solubility it was not possible to measure. HRMS (TOF MS

ES+) m/z [M + H]⁺calcd for C₁₅H₉O₂F₂259.0578, found 259.0571.

6-Fluoro-3-(p-tolyl)-4H-chromen-4-one (5m). The title com-

pound was prepared starting from ortho-hydroxyarylenaminone 1d

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 5:1 as eluent to provide

corresponding chromone. R_f= 0.4 (Hex:EtAc 3:1).

Yellow solid, mp 195−196 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.21

(d, 1H, ³J = 8.9 Hz), 7.99 (s, 1H), 7.69 (s, 4H), 7.01 (dd, 1H, ³J = 8.7

Hz, ⁴J = 2.5 Hz), 6.87 (d, 1H, ⁴J = 2.5 Hz), 3.92 (s, 3H). ¹³C{¹H} NMR

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(209 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)sulfonium

salt 2b (393 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg, 1.5 mmol,

1.5 equiv) and the dry DMF (0.3 mmol/mL). The puriﬁcation of the

dry crude performed by column chromatography on silica gel provides

the desired chromone 5m (226 mg, 0.89 mmol, 89%). The gram scale

synthesis was performed on 10 and 20 mmol of the starting ortho-

hydroxyarylenaminone and desired 5n was prepared in 85% (2.16 g, 8.5

mmol) and 80% (4.06 g, 16 mmol) yields, respectively.

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1d (209 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3b (636 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5m (221 mg, 0.87 mmol, 87%). The gram scale synthesis was

performed on 10 and 20 mmol of the starting ortho-hydroxyarylena-

minone and desired 5n was prepared in 77% (1.96 g, 7.7 mmol) and

78% (3.96 g, 15.6 mmol) yields, respectively.

Alternatively the title compound was prepared starting from

Ir[dF(CF₃)ppy]₂(dtbbpy)PF₆(11 mg, 0.01 mmol, 0.01 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1d (209 mg, 1.0 mmol, 1.0 equiv), and appropriate

triarylsulfonium salt 3d (699 mg, 1.5 mmol, 1.5 equiv) and dry DMSO

(0.2 mmol/mL). The puriﬁcation of the dry crude performed by

column chromatography on silica gel provides the desired chromone

5m (226 mg, 0.89 mmol, 89%).

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5o (238 mg, 0.88 mmol, 88%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6g (223 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4j (372 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5o (230 mg, 0.85 mmol, 85%). The gram scale synthesis was

performed on 10 mmol of the starting O-alkylated ortho-hydroxyar-

ylenaminone and desired 5o was prepared in 79% (2.13 g, 7.9 mmol)

yields.

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1d (209 mg, 1.0 mmol, 1.0 equiv), and appropriate

arenesulfonyl chloride 4j (372 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5o (130 mg, 0.48 mmol, 48%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 3:1 as eluent to provide

corresponding chromone. R_f= 0.45 (Hex:EtAc 3:1).

White solid, mp 133−134 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.03

(s, 1H), 7.92 (dd, 1H, ³J = 8.5 Hz, ⁴J = 3.0 Hz), 7.47−7.50 (m, 1H),

7.38−7.41 (m, 1H), 7.34 (t, 1H, ³J = 8.1 Hz), 7.13−7.14 (m, 1H), 7.10

(d, 1H, ³J = 7.5 Hz), 6.92 (dd, 1H, ³J = 8.0 Hz, ⁴J = 2.3 Hz), 3.83 (s 3H).

In all previous cases gradient ﬂash column chromatography was

performed using a mixture of hexane/ethyl acetate 7:1 to 5:1 as eluent

to provide corresponding chromone. R_f= 0.65 (Hex:EtAc 3:1).

White solid, mp 160−161 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.00

(s, 1H), 7.93 (dd, 1H, ³J = 8.2 Hz, ⁴J = 3.2 Hz), 7.47−7.50 (m, 1H),

7.45 (d, 2H, ³J = 8.2 Hz), 7.37−7.41 (m, 1H), 7.25 (d, 2H, ³J = 8.0 Hz),

2.39 (s, 3H). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ 175.5, 159.5 (d, ¹J_CF

= 248.6 Hz), 152.9, 152.3, 138.1, 129.2, 128.7, 128.4, 125.6 (d, J_CF= 7.1

Hz), 124.5, 121.7 (d, J_CF= 25.7 Hz), 120.0 (d, J_CF= 7.1 Hz), 111.0 (d,

1

¹³C{¹H} NMR (126 MHz, CDCl₃) δ 175.3, 159.54 (d, J_CF= 249.7

Hz), 159.5, 153.3, 152.3, 132.7, 129.5, 125.6 (d, J_CF= 7.3 Hz), 124.4,

121.8 (d, J_CF= 25.9 Hz), 121.1, 120.1 (d, J_CF= 7.6 Hz), 114.2 (d, J_CF

=

48.0 Hz), 111.0 (d, J_CF= 24.0 Hz), 55.2. MS (GC, 70 eV) m/z (%) =

270 (M⁺, 100), 239 (24), 170 (11), 132 (12), 89 (15). Anal. Calcd for

C₁₆H₁₁FO₃: C, 71.11; H, 4.10. Found: C, 71.03; H, 4.19.

3-(4-Chlorophenyl)-6-ﬂuoro-4H-chromen-4-one (5p). The

title compound was prepared starting from ortho-hydroxyarylenami-

none 1d (209 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)-

sulfonium salt 2g (333 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg,

1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5p (222 mg, 0.81 mmol, 81%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1d (209 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3e (722 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5p (233 mg, 0.85 mmol, 85%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6g (223 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4o (380 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5p (220 mg, 0.80 mmol, 80%).

J

_CF= 22.1 Hz), 21.2. MS (GC, 70 eV) m/z (%) = 254 (M⁺, 85), 253

(100), 126 (19), 115 (42), 110 (14). Anal. Calcd for C₁₆H₁₁FO₂: C,

75.58; H, 4.36. Found: C, 75.63; H, 4.41.

3-(4-(tert-Butyl)phenyl)-6-ﬂuoro-4H-chromen-4-one (5n).

The title compound was prepared starting from ortho-hydroxyarylena-

minone 1d (209 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl-

(aryl)sulfonium salt 2m (447 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃

(487 mg, 1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5n (246 mg, 0.83 mmol, 83%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1d (209 mg, 1.0 mmol, 1.0 equiv), and appropriate

triarylsulfonium salt 3h (714 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5n (228 mg, 0.77 mmol, 77%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 7:1−5:1 as eluent to provide

corresponding chromone. R_f= 0.6 (Hex:EtAc 5:1).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1d (209 mg, 1.0 mmol, 1.0 equiv), and appropriate

arenesulfonyl chloride 4o (380 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5p (159 mg, 0.58 mmol, 58%).

White solid, mp 160−162 °C. ¹H NMR (500 MHz, CDCl₃): 8.03 (s,

1H), 7.95 (dd, 1H, ³J = 8.2 Hz, ⁴J = 2.9 Hz), 7.47−7.52 (m, 5H), 7.39−

7.43 (m, 1H), 1.14 (s, 9H). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ 175.6,

159.6 (d, ¹J_CF= 247.2 Hz), 153.0, 152.4, 151.4, 128.6, 128.5, 125.6 (d,

J

_CF= 8.3 Hz), 125.6, 124.6, 121.8 (d, ¹J_CF= 25.6 Hz), 120.1 (d, J_CF= 8.5

Hz), 111.2 (d, J_CF= 22.6 Hz), 34.7, 31.2. HRMS (TOF MS ES+) m/z

[M + H]⁺calcd for C₁₉H₁₈O₂F 297.1292, found 297.1291.

6-Fluoro-3-(3-methoxyphenyl)-4H-chromen-4-one (5o). The

title compound was prepared starting from ortho-hydroxyarylenami-

none 1d (209 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)-

sulfonium salt 2g (333 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg,

1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/mL). The

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 5:1 as eluent to provide

corresponding chromone. R_f= 0.5 (Hex:EtAc 3:1).

White solid, mp 191−192 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.03

(s, 1H), 7.93 (dd, 1H, ³J = 8.2 Hz, ⁴J = 2.8 Hz), 7.50−7.52 (m, 3H),

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7.41−7.45 (m, 3H). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ 175.3, 160.7,

Hz), 7.55 (d, 2H, ³J = 7.1 Hz), 7.44−7.47 (m, 3H), 7.39−7.42 (m, 1H).

¹³C{¹H} NMR (126 MHz, CDCl₃) δ 175.1, 154.5, 153.2, 133.9, 131.4,

131.2, 128.9, 128.6, 128.4, 125.8, 125.5, 125.4, 119.8. MS (GC, 70 eV)

m/z (%) = 256 (M⁺, 75), 255 (100), 154 (26), 126 (31), 102 (20).

Anal. Calcd for C₁₅H₉ClO₂: C, 70.19; H, 3.53. Found: C, 70.03; H,

3.59.

6-Chloro-3-(4-chlorophenyl)-4H-chromen-4-one (5s). The

title compound was prepared starting from ortho-hydroxyarylenami-

none 1f (226 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)-

sulfonium salt 2j (419 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg,

1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5s (247 mg, 0.85 mmol, 85%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1f (226 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3e (722 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5s (250 mg, 0.86 mmol, 86%).

153.4 (d, ¹J_CF= 253.0 Hz), 153.2, 134.4, 130.2, 129.9, 128.8, 125.5 (d,

J_CF= 7.9 Hz), 123.7, 122.2 (d, J_CF= 25.9 Hz), 120.2 (d, J_CF= 7.9 Hz),

111.1 (d, J_CF= 28.0 Hz), 109.0, 104.1. HRMS (TOF MS ES+) m/z [M

+ H]⁺calcd for C₁₅H₉O₂FCl 275.0275, found 275.0275.

7-Fluoro-3-(naphthalen-1-yl)-4H-chromen-4-one (5q). The

title compound was prepared starting from ortho-hydroxyarylenami-

none 1e (209 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)-

sulfonium salt 2d (439 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg,

1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5q (223 mg, 0.77 mmol, 77%).

The gram scale synthesis was performed on 10 mmol of the starting

ortho-hydroxyarylenaminone and desired 5q was prepared in 78% (2.26

g, 7.8 mmol) yields.

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6h (223 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4c (408 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5q (235 mg, 0.81 mmol, 81%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1e (209 mg, 1.0 mmol, 1.0 equiv), and appropriate

arenesulfonyl chloride 4c (408 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5q (93 mg, 0.32 mmol, 32%).

In all previous cases gradient ﬂash column chromatography was

performed using a mixture of hexane/ethyl acetate 7:1 to 3:1 as eluent

to provide corresponding chromone. R_f= 0.6 (Hex:EtAc 3:1).

Yellow solid, mp 134−135 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.35−

8.37 (m, 1H), 8.00 (s, 1H), 7.90−7.94 (m, 2H), 7.74 (d, 1H, ³J = 8.3

Hz), 7.42−7.55 (m, 4H), 7.19−7.24 (m, 2H). ¹³C{¹H} NMR (126

MHz, CDCl₃) δ 175.6, 165.6 (d, ¹J_CF= 256.1 Hz), 157.3 (d, J_CF= 13.2

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6i (240 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4o (381 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5s (247 mg, 0.85 mmol, 85%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 10:1 as eluent to provide

corresponding chromone. R_f= 0.45 (Hex:EtAc 5:1).

Yellow solid, mp 179−180 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.27

(d, 1H, ⁴J = 2.6 Hz), 8.02 (s, 1H), 7.63 (dd, 1H, ³J = 8.9 Hz, ⁴J = 2.6

Hz), 7.50 (d, 2H, ³J = 8.5 Hz), 7.46 (d, 1H, ³J = 9.0 Hz), 7.42 (d, 2H, ³J

= 8.5 Hz). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ 174.9, 154.5, 153.1,

134.5, 134.1, 131.4, 130.2, 129.8, 128.8, 125.8, 125.4, 124.4, 119.9.

HRMS (TOF MS ES+) m/z [M + H]⁺calcd for C₁₅H₉O₂Cl₂290.9983,

found 290.9980.

Hz), 154.2, 133.6, 132.3, 129.3, 129.0 (d, J_CF= 9.9 Hz), 128.2 (d, J_CF

=

22.6 Hz), 126.3, 126.0, 125.5, 125.3 (d, ¹J_CF= 24.4 Hz), 121.2, 114.1 (d,

6-Chloro-3-(p-tolyl)-4H-chromen-4-one (5t). The title com-

pound was prepared starting from ortho-hydroxyarylenaminone 1f (226

mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)sulfonium salt 2b

(393 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg, 1.5 mmol, 1.5

equiv) and the dry DMF (0.3 mmol/mL). The puriﬁcation of the dry

crude performed by column chromatography on silica gel provides the

desired chromone 5t (225 mg, 0.83 mmol, 83%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1f (226 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3b (636 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5t (230 mg, 0.85 mmol, 85%).

J

_CF= 23.1 Hz), 104.6 (d, J_CF= 26.0 Hz). HRMS (TOF MS ES+) m/z

[M + H]⁺calcd for C₁₉H₁₂O₂F 291.0826, found 291.0821.

6-Chloro-3-phenyl-4H-chromen-4-one (5r). The title com-

pound was prepared starting from ortho-hydroxyarylenaminone 1f

(226 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)sulfonium

salt 2a (374 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg, 1.5 mmol,

1.5 equiv) and the dry DMF (0.3 mmol/mL). The puriﬁcation of the

dry crude performed by column chromatography on silica gel provides

the desired chromone 5r (233 mg, 0.91 mmol, 91%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1f (226 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3a (577 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5r (238 mg, 0.93 mmol, 93%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6i (240 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4a (318 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5r (233 mg, 0.91 mmol, 91%).

In all previous cases gradient ﬂash column chromatography was

performed using a mixture of hexane/ethyl acetate 8:1 to 7:1 as eluent

to provide corresponding chromone. R_f= 0.6 (Hex:EtAc 3:1).

White solid, mp 179−180 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.27

(d, 1H, ⁴J = 2.6 Hz), 8.02 (s, 1H), 7.63 (dd, 1H, ³J = 8.9 Hz, ⁴J = 2.6

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 10:1 as eluent to provide

corresponding chromone. R_f= 0.6 (Hex:EtAc 5:1).

White solid, mp 175−176 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.26

(d, 1H, ⁴J = 2.5 Hz), 8.00 (s, 1H), 7.61 (dd, 1H, ³J = 8.9 Hz, ⁴J = 2.6

3

Hz), 7.43−7.45 (m, 3H), 7.25 (d, 2H, J = 8.1 Hz), 2.40 (s, 3H).

¹³C{¹H} NMR (126 MHz, CDCl₃) δ 175.2, 154.5, 152.9, 138.3, 131.1,

129.3, 128.7, 128.4, 125.7, 125.4, 125.3, 119.8, 21.2. HRMS (TOF MS

ES+) m/z [M + H]⁺calcd for C₁₆H₁₂O₂Cl 271.0526, found 271.0526.

6-Chloro-3-(o-tolyl)-4H-chromen-4-one (5u). The title com-

pound was prepared starting from ortho-hydroxyarylenaminone 1f (226

mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)sulfonium salt 2c

(393 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg, 1.5 mmol, 1.5

equiv) and the dry DMF (0.3 mmol/mL). The puriﬁcation of the dry

crude performed by column chromatography on silica gel provides the

desired chromone 5u (216 mg, 0.80 mmol, 80%).

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The ﬂash column chromatography was performed using a mixture of

hexane/ethyl acetate 7:1−5:1 as eluent to provide corresponding

chromone. R_f= 0.7 (Hex:EtAc 3:1).

In all previous cases gradient ﬂash column chromatography was

performed using a mixture of hexane/ethyl acetate 7:1 to 5:1 as eluent

to provide corresponding chromone. R_f= 0.75 (Hex:EtAc 3:1).

Yellow solid, mp 107−109 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.24

(s, 1H), 7.96 (s, 1H), 7.32−7.36 (m, 4H), 7.21 (br. s, 1H), 2.51 (s, 3H),

2.40 (s, 3H). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ 175.1, 154.4, 152.9,

142.8, 138.1, 131.9, 131.4, 129.6, 129.1, 128.4, 126.0, 125.9, 125.3,

123.6, 119.8, 21.5, 20.8. HRMS (TOF MS ES+) m/z [M + H]⁺calcd

for C₁₇H₁₄O₂Cl 285.0685, found 285.0682.

3-(2-Bromophenyl)-6-chloro-7-methyl-4H-chromen-4-one

(5y). The title compound was prepared starting from ortho-

hydroxyarylenaminone 1g (240 mg, 1.0 mmol, 1.0 equiv), appropriate

dimethyl(aryl)sulfonium salt 2k (407 mg, 1.3 mmol, 1.3 equiv), and

Cs₂CO₃(487 mg, 1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/

mL). The puriﬁcation of the dry crude performed by column

chromatography on silica gel provides the desired chromone 5y (167

mg, 0.67 mmol, 67%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1g (240 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3j (833 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5y (182 mg, 0.73 mmol, 73%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1g (240 mg, 1.0 mmol, 1.0 equiv) and appropriate

arenesulfonyl chloride 4f (461 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5y (82 mg, 0.33 mmol, 33%).

White solid, mp 131−132 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.26

(d, 1H, ⁴J = 2.5 Hz), 7.89 (s, 1H), 7.63 (d, 1H, ³J = 8.9 Hz, ⁴J = 2.6 Hz),

7.47 (d, 1H, ³J = 8.9 Hz), 7.29−7.34 (m, 2H), 7.43 (d, 1H, ³J = 8.5 Hz),

7.23−7.35 (m, 1H), 7.17 (d, 1H, ³J = 7.1 Hz), 2.25 (s, 3H). ¹³C{¹H}

NMR (126 MHz, CDCl₃) δ 174.8, 154.7, 153.7, 138.0, 133.9, 131.2,

131.1, 130.4, 130.3, 128.8, 126.5, 125.8, 125.7, 125.3, 119.9, 20.0.

HRMS (TOF MS ES+) m/z [M + H]⁺: C₁₆H₁₂O₂Cl 271.0533, found

271.0526.

6-Chloro-7-methyl-3-(3-(triﬂuoromethyl)phenyl)-4H-chro-

men-4-one (5v). The title compound was prepared starting from

ortho-hydroxyarylenaminone 1f (226 mg, 1.0 mmol, 1.0 equiv),

appropriate dimethyl(aryl)sulfonium salt 2e (463 mg, 1.3 mmol, 1.3

equiv), and Cs₂CO₃(487 mg, 1.5 mmol, 1.5 equiv) and the dry DMF

(0.3 mmol/mL). The puriﬁcation of the dry crude performed by

column chromatography on silica gel provides the desired chromone 5v

(264 mg, 0.78 mmol, 78%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1g (240 mg, 1.0 mmol, 1.0 equiv) and appropriate

arenesulfonyl chloride 4h (440 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5v (203 mg, 0.60 mmol, 60%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 5:1 as eluent to provide

corresponding chromone. R_f= 0.5 (Hex:EtAc 3:1).

Yellow solid, mp 162−163 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.23

(s, 1H), 8.03 (s, 1H), 7.80 (s, 1H), 7.76 (m, 1H, ³J = 7.9 Hz), 7.64 (d,

1H, ³J = 7.9 Hz), 7.56 (t, 1H, ³J = 7.9 Hz), 7.39 (s, 1H), 2.52 (s, 3H).

¹³C{¹H} NMR (126 MHz, CDCl₃) δ 174.7, 154.4, 153.4, 143.4, 132.3

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 10:1 as eluent to provide

corresponding chromone. R_f= 0.65 (Hex:EtAc 5:1).

2

(m), 130.9 (q, J_CF= 32.0 Hz), 128.9, 125.9, 125.6 (m), 125.0 (m),

124.1, 124.5 (q, ¹J_CF= 267.9 Hz), 119.9, 20.9. HRMS (TOF MS ES+)

m/z [M + H]⁺calcd for C₁₇H₁₁O₂F₃Cl 339.0409, found 339.0400.

6-Chloro-7-methyl-3-(o-tolyl)-4H-chromen-4-one (5w). The

title compound was prepared starting from ortho-hydroxyarylenami-

none 1g (240 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)-

sulfonium salt 2c (393 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg,

1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5w (162 mg, 0.57 mmol, 57%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1g (240 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3c (636 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5w (199 mg, 0.70 mmol, 70%).

Light brown solid, mp 186−187 °C. ¹H NMR (500 MHz, CDCl₃) δ

8.24 (br. s, 1H, CH_Ar), 7.90 (s, 1H, CH_Ar), 7.67 (dd, 1H, ³J = 8.0 Hz, ⁴J

= 0.9 Hz, CH_Ar), 7.39 (s, 1H, CH_Ar), 7.36 (dd, 1H, ³J = 7.4 Hz, ⁴J = 1.1

Hz, CH_Ar), 7.30−7.33 (m, 1H, CH_Ar), 7.25−7.26 (m, 1H, CH_Ar), 2.51

(s, 3H, Me). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ 174.3, 154.6, 154.3,

143.1, 133.0, 132.6, 132.2, 132.1, 130.1, 127.4, 126.0, 125.7, 124.7,

123.5, 119.9, 20.8. MS (GC, 70 eV) m/z (%) = 347 (M⁺, 3), 269 (100),

178 (10), 117 (10), 88 (14). Anal. Calcd for C₁₆H₁₀BrClO₂: C, 54.97;

H, 2.88. Found: C, 55.00; H, 2.96.

3-(4-(Triﬂuoromethyl)phenyl)-4H-benzo[h]chromen-4-one

(5z). The title compound was prepared starting from ortho-

hydroxyarylenaminone 1h (241 mg, 1.0 mmol, 1.0 equiv), appropriate

dimethyl(aryl)sulfonium salt 2n (463 mg, 1.3 mmol, 1.3 equiv), and

Cs₂CO₃(487 mg, 1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/

mL). The puriﬁcation of the dry crude performed by column

chromatography on silica gel provides the desired chromone 5z (286

mg, 0.84 mmol, 84%). The gram scale synthesis was performed on 10

mmol of the starting ortho-hydroxyarylenaminone and desired 5z was

prepared in 80% (2.72 g, 8.0 mmol) yield.

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1h (241 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3g (862 mg, 1.4 mmol, 1.4 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5z (303 mg, 0.89 mmol, 89%). The gram scale synthesis was performed

on 10 mmol of the starting ortho-hydroxyarylenaminone and desired 5z

was prepared in 72% (2.45 g, 7.2 mmol) yield.

In all previous cases gradient ﬂash column chromatography was

performed using a mixture of hexane/ethyl acetate 10:1 to 7:1 as eluent

to provide corresponding chromone. R_f= 0.7 (Hex:EtAc 3:1).

Yellow solid, mp 160−161 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.24

(br. s, 1H), 7.84 (s, 1H), 7.39 (s, 1H), 7.28−7.32 (m, 2H), 7.23 (dt, 1H,

³J = 7.2 Hz, ⁴J = 1.2 Hz), 7.17 (dd, 1H, ³J = 7.5 Hz, ⁴J = 1.0 Hz), 2.51 (s,

3H), 2.25 (s, 3H). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ 174.7, 154.6,

153.4, 142.8, 137.9, 131.8, 131.2, 130.3, 130.1, 128.6, 126.2, 125.8,

125.7, 123.4, 119.8, 20.7, 19.9. HRMS (TOF MS ES+) m/z [M + H]⁺

calcd for C₁₇H₁₄O₂Cl 285.0688, found 285.0682.

6-Chloro-7-methyl-3-(m-tolyl)-4H-chromen-4-one (5x). The

title compound was prepared starting from ortho-hydroxyarylenami-

none 1g (240 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)-

sulfonium salt 2l (393 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg,

1.5 mmol, 1.5 equiv) and the dry DMF (0.3 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5x (250 mg, 0.88 mmol, 88%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6j (255 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4d (440 mg, 1.8 mmol, 1.8 equiv)

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and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5z (306 mg, 0.90 mmol, 90%). The gram scale synthesis was

performed on 10 mmol of the starting O-alkylated ortho-hydroxyar-

ylenaminone and desired 5z was prepared in 83% (2.82 g, 8.3 mmol)

yields.

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1h (241 mg, 1.0 mmol, 1.0 equiv) and appropriate

arenesulfonyl chloride 4d (440 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5z (184 mg, 0.54 mmol, 54%).

by column chromatography on silica gel provides the desired chromone

5ab (243 mg, 0.85 mmol, 85%).

In all previous cases gradient ﬂash column chromatography was

performed using a mixture of hexane/ethyl acetate 5:1 to 3:1 as eluent

to provide corresponding chromone. R_f= 0.6 (Hex:EtAc 3:1).

Yellow solid, mp 189−190 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.48

(d, 1H, ³J = 7.9 Hz), 8.24 (d, 1H, ³J = 8.5 Hz), 8.17 (s, 1H), 7.92 (d, 1H,

³J = 7.8 Hz), 7.76 (d, 1H, ³J = 8.5 Hz), 7.65−7.72 (m, 2H), 7.54 (d, 2H,

³J = 9.4 Hz), 7.28 (d, 2H, ³J = 7.9 Hz), 2.41 (s, 3H, Me). ¹³C{¹H} NMR

(126 MHz, CDCl₃) δ 176.1, 153.5, 151.9, 138.2, 135.7, 129.2, 127.8,

128.7, 128.0, 127.1, 126.4, 125.2, 123.9, 122.2, 121.3, 120.8, 21.3.

HRMS (TOF MS ES+) m/z [M + H]⁺calcd for C₂₀H₁₅O₂287.1074,

found 287.1072.

3-(2-(Triﬂuoromethoxy)phenyl)-4H-benzo[h]chromen-4-

one (5ac). The title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6j (255 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4l (469 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5ac (260 mg, 0.73 mmol, 73%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 10:1 as eluent to provide

corresponding chromone. R_f= 0.4 (Hex:EtAc 5:1).

Yellow solid, mp 230−231 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.52

3

(d, 1H, J = 7.7 Hz), 8.24−8.27 (m, 2H), 7.96 (d, 1H, J = 6.7 Hz),

7.71−7.83 (m, 7H). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ Due to bad

solubility it was not possible to measure. HRMS (TOF MS ES+) m/z

[M + H]⁺calcd for C₂₀H₁₂O₂F₃341.0795, found 341.0789.

3-(o-Tolyl)-4H-benzo[h]chromen-4-one (5aa). The title com-

pound was prepared starting from ortho-hydroxyarylenaminone 1h

(241 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)sulfonium

salt 2c (393 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg, 1.5 mmol,

1.5 equiv) and the dry DMF (0.3 mmol/mL). The puriﬁcation of the

dry crude performed by column chromatography on silica gel provides

the desired chromone 5aa (169 mg, 0.59 mmol, 59%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1h (241 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3c (636 mg, 1.5 mmol, 1.5 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5aa (206 mg, 0.72 mmol, 72%).

Alternatively the title compound was prepared starting from

Ir[dF(CF₃)ppy]₂(dtbbpy)PF₆(11 mg, 0.01 mmol, 0.01 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1h (241 mg, 1.0 mmol, 1.0 equiv), and appropriate

triarylsulfonium salt 3c (681 mg, 1.4 mmol, 1.4 equiv) and dry DMSO

(0.2 mmol/mL). The puriﬁcation of the dry crude performed by

column chromatography on silica gel provides the desired chromone

5aa (203 mg, 0.71 mmol, 71%).

In all previous cases gradient ﬂash column chromatography was

performed using a mixture of hexane/ethyl acetate 5:1 to 3:1 as eluent

to provide corresponding chromone. R_f= 0.6 (Hex:EtAc 3:1).

Yellow solid, mp 141−142 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.50

(d, 1H, ³J = 8.0 Hz), 8.25 (d, 1H, ³J = 8.5 Hz), 8.20 (s, 1H), 7.93 (d, 1H,

³J = 7.5 Hz), 7.78 (d, 1H, ³J = 8.8 Hz), 7.68−7.73 (m, 2H), 7.48 (s, 1H),

7.41 (d, 1H, ³J = 7.9 Hz), 7.37 (t, 1H, ³J = 7.4 Hz), 7.23 (d, 1H, ³J = 7.4

Hz), 2.43 (s, 3H). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ 176.1, 153.4,

152.2, 138.1, 135.7, 131.6, 129.7, 129.3, 129.1, 128.5, 128.1, 127.1,

126.7, 126.0, 125.3, 124.0, 122.2, 121.3, 120.9, 21.5. HRMS (TOF MS

ES+) m/z [M + H]⁺calcd for C₂₀H₁₅O₂287.1084, found 287.1072.

3-(p-Tolyl)-4H-benzo[h]chromen-4-one (5ab). The title com-

pound was prepared starting from ortho-hydroxyarylenaminone 1h

(241 mg, 1.0 mmol, 1.0 equiv), appropriate dimethyl(aryl)sulfonium

salt 2b (393 mg, 1.3 mmol, 1.3 equiv), and Cs₂CO₃(487 mg, 1.5 mmol,

1.5 equiv) and the dry DMF (0.3 mmol/mL). The puriﬁcation of the

dry crude performed by column chromatography on silica gel provides

the desired chromone 5ab (249 mg, 0.87 mmol, 87%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1h (241 mg, 1.0 mmol, 1.0 equiv) and appropriate

arenesulfonyl chloride 4l (469 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5ac (110 mg, 0.31 mmol, 31%).

In all previous cases gradient ﬂash column chromatography was

performed using a mixture of hexane/ethyl acetate 7:1 to 5:1 as eluent

to provide corresponding chromone. R_f= 0.5 (Hex:EtAc 3:1).

Yellow solid, mp 131−132 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.51

(d, 1H, ³J = 7.9 Hz), 8.23 (d, 1H, ³J = 8.9 Hz), 8.19 (s, 1H), 7.94 (d, 1H,

³J = 7.8 Hz), 7.79 (d, 1H, ³J = 8.7 Hz), 7.68−7.74 (m, 2H), 7.52 (dd,

1H, ³J = 7.5 Hz, ⁴J = 1.8 Hz), 7.45−7.49 (m, 1H), 7.38−7.41 (m, 2H).

¹³C{¹H} NMR (126 MHz, CDCl₃) δ 175.2, 153.7, 153.5, 147.3, 135.8,

132.5, 130.0, 129.4, 128.1, 126.8, 125.5, 125.2, 123.9, 122.9, 122.2,

121.2, 120.9, 120.4 (d, ¹J_CF= 258.8 Hz). HRMS (TOF MS ES+) m/z

[M + H]⁺calcd for C₂₀H₁₂O₃F₃357.0748, found 357.0739.

3-(3-(Triﬂuoromethoxy)phenyl)-4H-benzo[h]chromen-4-

one (5ad). The title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6j (255 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4k (469 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5ad (331 mg, 0.93 mmol, 93%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1h (241 mg, 1.0 mmol, 1.0 equiv) and appropriate

arenesulfonyl chloride 4k (469 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5ad (210 mg, 0.59 mmol, 59%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 5:1 as eluent to provide

corresponding chromone. R_f= 0.5 (Hex:EtAc 3:1).

Yellow solid, mp 117−118 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.46

(d, 1H, ³J = 8.1 Hz), 8.20−8.22 (m, 2H), 7.91 (d, 1H, ³J = 7.6 Hz), 7.76

(d, 1H, ³J = 8.6 Hz), 7.66−7.73 (m, 2H), 7.56−7.58 (m, 2H), 7.48 (t,

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

NaOAc (148 mg, 1.8 mmol, 1.8 equiv) appropriate ortho-hydroxyar-

ylenaminone 1h (241 mg, 1.0 mmol, 1.0 equiv) and appropriate

triarylsulfonium salt 3b (636 mg, 1.5 mmol, 1.5 equiv) and the dry

CH₃CN (0.12 mmol/mL). The puriﬁcation of the dry crude performed

3

1H, J = 7.9 Hz), 7.26−7.27 (m, 1H). ¹³C{¹H} NMR (126 MHz,

CDCl₃) δ 175.5, 153.5, 152.5, 149.3, 135.8, 133.7, 129.8, 129.4, 128.1,

127.3, 127.2, 125.6, 125.1, 123.8, 122.1, 121.6, 121.0, 120.7, 120.6,

120.5 (d, ¹J_CF= 256.5 Hz). HRMS (TOF MS ES+) m/z [M + H]⁺calcd

for C₂₀H₁₂O₃F₃357.0742, found 357.0739.

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Article

3-(3,5-Dichlorophenyl)-6-methyl-4H-chromen-4-one (5ae).

The title compound was prepared starting from photocatalyst

Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv), Na₂CO₃(212

mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyarylenaminone 1b

(205 mg, 1.0 mmol, 1.0 equiv), and appropriate arenesulfonyl chloride

4q (442 mg, 1.8 mmol, 1.8 equiv) and dry CH₃CN (0.10 mmol/mL).

The puriﬁcation of the dry crude performed by column chromatog-

raphy on silica gel provides the desired chromone 5ae (186 mg, 0.61

mmol, 61%).

hydroxyarylenaminone 6i (240 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4k (469 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5ah (306 mg, 0.90 mmol, 90%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1f (226 mg, 1.0 mmol, 1.0 equiv) and appropriate

arenesulfonyl chloride 4k (469 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5ah (167 mg, 0.49 mmol, 49%).

The ﬂash column chromatography was performed using a mixture of

hexane/ethyl acetate 10:1 as eluent to provide corresponding

chromone. R_f= 0.55 (Hex:EtAc 5:1).

Yellow solid, mp 115−116 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.02

(br. s, 1H), 7.99 (s, 1H), 7.48 (dd, 1H, ³J = 8.6 Hz, ⁴J = 1.8 Hz), 7.44 (d,

2H, ⁴J = 1.8 Hz), 7.36 (d, 1H, ³J = 8.6 Hz), 7.31 (t, 1H, ⁴J = 1.8 Hz),

3.45 (s, 3H). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ 175.4, 154.3, 153.5,

135.6, 135.2, 134.8, 128.0, 127.2, 125.5, 123.9, 122.8, 117.8, 20.9.

HRMS (TOF MS ES+) m/z [M + H]⁺calcd for C₁₆H₁₁O₂Cl₂

305.0140, found 305.0136.

In all previous cases gradient ﬂash column chromatography was

performed using a mixture of hexane/ethyl acetate 7:1 to 5:1 as eluent

to provide corresponding chromone. R_f= 0.7 (Hex:EtAc 3:1).

1

Light yellow solid, mp 94−95 °C. H NMR (500 MHz, CDCl₃) δ

8.26 (d, 1H, ⁴J = 2.5 Hz), 8.05 (s, 1H), 7.64 (dd, 1H, ³J = 9.2 Hz, ⁴J = 2.5

Hz), 7.46−7.51 (m, 4H), 7.25−7.26 (m, 1H). ¹³C{¹H} NMR (126

MHz, CDCl₃) δ 174.7, 154.5, 153.5, 149.3, 134.2, 133.3, 131.5, 129.9,

127.2, 125.8, 125.4, 119.9, 124.1, 121.5, 120.8, 120.5 (d, ¹J_CF= 258.5

Hz). HRMS (TOF MS ES+) m/z [M + H]⁺calcd for C₁₆H₉O₃F₃Cl

341.0203, found 341.0192.

6-Chloro-3-(3-methoxyphenyl)-4H-chromen-4-one (5af).

The title compound was prepared starting from photocatalyst

Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv), Na₂CO₃(212

mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-hydroxyarylena-

minone 6i (240 mg, 1.0 mmol, 1.0 equiv) and appropriate arenesulfonyl

chloride 4j (372 mg, 1.8 mmol, 1.8 equiv) and dry CH₃CN (0.10

mmol/mL). The puriﬁcation of the dry crude performed by column

chromatography on silica gel provides the desired chromone 5af (242

mg, 0.84 mmol, 84%).

6-Chloro-3-(m-tolyl)-4H-chromen-4-one (5ai). The title com-

pound was prepared starting from photocatalyst Ru(bpy)₃Cl₂·6H₂O

(15.0 mg, 0.02 mmol, 0.02 equiv), Na₂CO₃(212 mg, 2 mmol, 2 equiv),

appropriate O-alkylated ortho-hydroxyarylenaminone 6i (240 mg, 1.0

mmol, 1.0 equiv) and appropriate arenesulfonyl chloride 4p (343 mg,

1.8 mmol, 1.8 equiv) and dry CH₃CN (0.10 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography

on silica gel provides the desired chromone 5ai (235 mg, 0.87 mmol,

87%).

The column chromatography was performed using a mixture of

hexane/ethyl acetate 7:1 to 5:1 as eluent to provide corresponding

chromone. R_f= 0.5 (Hex:EtAc 5:1).

Light yellow solid, mp 126−127 °C. ¹H NMR (500 MHz, CDCl₃) δ

8.25 (d, 1H, ⁴J = 2.5 Hz), 8.01 (s, 1H), 7.60 (dd, 1H, ³J = 8.8 Hz, ⁴J = 2.6

Hz), 7.43 (d, 1H, ³J = 8.9 Hz), 7.34 (t, 1H, ³J = 7.9 Hz), 7.08−7.13 (m,

The gradient ﬂash column chromatography was performed using a

mixture of hexane/ethyl acetate 5:1 as eluent to provide corresponding

chromone. R_f= 0.5 (Hex:EtAc 3:1).

3

4

2H), 6.93 (dd, 1H, J = 8,3 Hz, J = 2.6 Hz), 3.84 (s, 3H). ¹³C{¹H}

NMR (126 MHz, CDCl₃) δ 175.0, 159.6, 154.4, 153.2, 133.8, 132.6,

131.2, 129.5, 125.7, 125.4, 125.2, 121.1, 119.8, 114.4, 114.1, 55.3.

HRMS (TOF MS ES+) m/z [M + H]⁺calcd for C₁₆H₁₂O₃Cl 287.0478,

found 287.0475.

1

Light yellow solid, mp 94−95 °C. H NMR (500 MHz, CDCl₃) δ

8.25 (d, 1H, ⁴J = 2.6 Hz), 8.00 (s, 1H), 7.60 (dd, 1H, ³J = 8.9 Hz, ⁴J = 2.7

Hz), 7.43 (d, 1H, ³J = 8.5 Hz), 7.37 (s, 1H), 7.33−7.34 (m, 2H), 7.21−

7.22 (m, 1H), 2.41 (s, 3H). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ 175.1,

154.5, 153.1, 138.2, 133.8, 131.2, 131.1, 129.6, 129.2, 128.5, 125.9,

125.7, 125.5, 125.4, 119.8, 21.5. HRMS (TOF MS ES+) m/z [M + H]⁺

calcd for C₁₆H₁₂O₂Cl 271.0524, found 271.0526.

6-Chloro-3-(2-(triﬂuoromethoxy)phenyl)-4H-chromen-4-

one (5ag). The title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6i (240 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4l (469 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5ag (242 mg, 0.71 mmol, 71%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1f (226 mg, 1.0 mmol, 1.0 equiv) and appropriate

arenesulfonyl chloride 4l (469 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5ag (119 mg, 0.35 mmol, 35%).

6-Chloro-3-(4-(triﬂuoromethoxy)phenyl)-4H-chromen-4-

one (5aj). The title compound was prepared starting from photo-

catalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv), Na₂CO₃

(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

hydroxyarylenaminone 6i (240 mg, 1.0 mmol, 1.0 equiv) and

appropriate arenesulfonyl chloride 4s (469 mg, 1.8 mmol, 1.8 equiv)

and dry CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude

performed by column chromatography on silica gel provides the desired

chromone 5aj (283 mg, 0.83 mmol, 83%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1f (226 mg, 1.0 mmol, 1.0 equiv) and appropriate

arenesulfonyl chloride 4s (469 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5aj (180 mg, 0.53 mmol, 53%).

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 8:1 as eluent to provide

corresponding chromone. R_f= 0.5 (Hex:EtAc 3:1).

Light brown solid, mp 140−141 °C. ¹H NMR (500 MHz, CDCl₃) δ

8.25 (d, 1H, ⁴J = 2.1 Hz), 7.98 (s, 1H), 7.63 (dd, 1H, ³J = 8.4 Hz, ⁴J = 2.1

Hz), 7.43−7.48 (m, 3H), 7.35−7.38 (m, 2H). ¹³C{¹H} NMR (126

MHz, CDCl₃) δ 174.3, 154.6, 154.4, 147.3, 134.0, 132.4, 131.4, 130.1,

In all previous cases gradient ﬂash column chromatography was

performed using a mixture of hexane/ethyl acetate 7:1 to 5:1 as eluent

to provide corresponding chromone. R_f= 0.7 (Hex:EtAc 3:1).

Light yellow solid, mp 162−163 °C. ¹H NMR (500 MHz, CDCl₃) δ

8.26 (d, 1H, ⁴J = 2.6 Hz), 8.03 (s, 1H), 7.64 (dd, 1H, ³J = 9.0 Hz, ⁴J = 2.5

Hz), 7.58−7.61 (m, 2H), 7.46 (d, 1H, ³J = 9.0 Hz), 7.29 (d, 2H, ³J = 8.2

Hz). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ 174.9, 154.5, 153.2, 149.3,

1

126.8, 125.7, 125.2, 124.7, 121.5, 120.8, 120.3 (d, J_CF= 261.4 Hz),

119.9. HRMS (TOF MS ES+) m/z [M + H]⁺calcd for C₁₆H₉O₃F₃Cl

341.0197, found 341.0192.

6-Chloro-3-(3-(triﬂuoromethoxy)phenyl)-4H-chromen-4-

one (5ah). The title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-

134.1, 131.5, 130.4, 130.0, 125.8, 125.4, 124.3, 121.1, 120.4 (d, ¹J_CF

=

257.7 Hz), 119.9. HRMS (TOF MS ES+) m/z [M + H]⁺calcd for

C₁₆H₉O₃F₃Cl 341.0197, found 341.0192.

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Article

3-(4-Phenoxyphenyl)-4H-chromen-4-one (5ak). The title

compound was prepared starting from photocatalyst Ru(bpy)₃Cl₂·

6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv), Na₂CO₃(212 mg, 2 mmol, 2

equiv), appropriate O-alkylated ortho-hydroxyarylenaminone 6a (205

mg, 1.0 mmol, 1.0 equiv) and appropriate arenesulfonyl chloride 4i

(550 mg, 1.8 mmol, 1.8 equiv) and dry CH₃CN (0.10 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5ak (206 mg, 0.62 mmol,

62%).

Alternatively, the title compound was prepared starting from

photocatalyst Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv),

Na₂CO₃(212 mg, 2 mmol, 2 equiv), appropriate ortho-hydroxyar-

ylenaminone 1a (191 mg, 1.0 mmol, 1.0 equiv), and appropriate

arenesulfonyl chloride 4i (550 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5ak (163 mg, 0.49 mmol, 49%).

3-(4-Ethoxyphenyl)-6-ﬂuoro-4H-chromen-4-one (5an). The

title compound was prepared starting from photocatalyst Ru(bpy)₃Cl₂·

6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv), Na₂CO₃(212 mg, 2 mmol, 2

equiv), appropriate O-alkylated ortho-hydroxyarylenaminone 6g (223

mg, 1.0 mmol, 1.0 equiv) and appropriate arenesulfonyl chloride 4t

(397 mg, 1.8 mmol, 1.8 equiv) and dry CH₃CN (0.10 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5an (239 mg, 0.84 mmol,

84%).

The ﬂash column chromatography was performed using a mixture of

hexane/ethyl acetate 5:1 to 3:1 as eluent to provide corresponding

chromone. R_f= 0.5 (Hex:EtAc 3:1).

White solid, mp 163−164 °C. ¹H NMR (500 MHz, CDCl₃) δ 7.99

(s, 1H), 7.92 (dd, 1H, ³J = 8.2 Hz, ⁴J = 3.1 Hz), 7.46−7.49 (m, 3H),

3

7.35−7.41 (m, 1H), 6.95 (d, 2H, J = 8.6 Hz), 4.05 (q, 2H, J = 6.8

Hz),1.43 (t, 3H, J = 6.8 Hz). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ

3

175.6, 159.5 (d, ¹J_CF= 245.8 Hz), 159.0, 152.7, 152.3, 130.0, 125.5 (d,

J

_CF= 6.3 Hz), 124.3, 123.4, 121.7 (d, J_CF= 25.4 Hz), 120.1 (d, J_CF= 7.6

In all previous cases ﬂash column chromatography was performed

using a mixture of hexane/ethyl acetate 5:1 as eluent to provide

corresponding chromone. R_f= 0.5 (Hex:EtAc 3:1).

Hz), 111.0 (d, J_CF= 25.6 Hz), 63.4, 14.8. MS (GC, 70 eV) m/z (%) =

284 (M⁺, 100), 255 (98), 199 (12), 139 (20), 118 (39). Anal. Calcd for

C₁₇H₁₃FO₃: C, 71.82; H, 4.61. Found: C, 71.77; H, 4.53.

White solid, mp 158−159 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.32

(dd, 1H, ³J = 8.1 Hz, ⁴J = 1.3 Hz), 8.03 (s, 1H), 7.67−7.70 (m, 1H),

7.54 (d, 2H, ³J = 8.5 Hz), 7.48 (d, 1H, ³J = 8.5 Hz), 7.43 (t, 1H, ³J = 7.9

Hz), 7.36 (d, 2H, ³J = 7.6 Hz), 7.13 (t, 1H, ³J = 7.4 Hz), 7.06−7.08 (m,

4H). ¹³C{¹H} NMR (126 MHz, CDCl₃) δ 176.3, 157.4, 156.8, 156.1,

152.7, 133.6, 130.3, 129.7, 126.6, 126.3, 125.2, 124.7, 124.4, 123.5,

119.2, 118.6, 118.0. MS (GC, 70 eV) m/z (%) = 314 (M⁺, 100), 194

(25), 165 (21), 77 (12). Anal. Calcd for C₂₁H₁₄O₃: C, 80.24; H, 4.49.

Found: C, 80.32; H, 4.41.

7-Fluoro-3-(o-tolyl)-4H-chromen-4-one (5ao). The title com-

pound was prepared starting from photocatalyst Ru(bpy)₃Cl₂·6H₂O

(15.0 mg, 0.02 mmol, 0.02 equiv), Na₂CO₃(212 mg, 2 mmol, 2 equiv),

appropriate O-alkylated ortho-hydroxyarylenaminone 6h (223 mg, 1.0

mmol, 1.0 equiv) and appropriate arenesulfonyl chloride 4m (343 mg,

1.8 mmol, 1.8 equiv) and dry CH₃CN (0.10 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography

on silica gel provides the desired chromone 5ao (165 mg, 0.65 mmol,

65%).

6-Fluoro-3-(4-phenoxyphenyl)-4H-chromen-4-one (5al). The

title compound was prepared starting from photocatalyst Ru(bpy)₃Cl₂·

6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv), Na₂CO₃(212 mg, 2 mmol, 2

equiv), appropriate O-alkylated ortho-hydroxyarylenaminone 6g (223

mg, 1.0 mmol, 1.0 equiv) and appropriate arenesulfonyl chloride 4i

(483 mg, 1.8 mmol, 1.8 equiv) and dry CH₃CN (0.10 mmol/mL). The

puriﬁcation of the dry crude performed by column chromatography on

silica gel provides the desired chromone 5al (262 mg, 0.79 mmol, 79%).

The gradient ﬂash column chromatography was performed using a

mixture of hexane/ethyl acetate 7:1 to 5:1 as eluent to provide

corresponding chromone. R_f= 0.6 (Hex:EtAc 3:1).

The ﬂash column chromatography was performed using a mixture of

hexane/ethyl acetate 7:1 to 5:1 as eluent to provide corresponding

chromone. R_f= 0.7 (Hex:EtAc 3:1).

Light brown solid, mp 163−164 °C. ¹H NMR (500 MHz, CDCl₃) δ

8.30−8.33 (m, 1H), 7.86 (s, 1H), 7.29−7.33 (m, 2H), 7.23−7.26 (m,

1H),.7.15−7.20 (m, 3H), 2.26 (s, 3H). ¹³C{¹H} NMR (126 MHz,

CDCl₃) δ 175.1, 165.5 (d, ¹J_CF= 258.4 Hz), 157.3 (d, J_CF= 13.9 Hz),

153.6, 138.0, 131.1, 130.2 (d, J_CF= 25.9 Hz), 128.9 (d, ¹J_CF= 10.9 Hz),

128.7, 126.6, 125.8, 121.1, 104.6 (d, J_CF= 26.1 Hz), 114.0 (d, J_CF= 22.1

Hz), 20.0. HRMS (TOF MS ES+) m/z [M + H]⁺calcd for C₁₆H₁₂O₂F

255.0832, found 255.0821.

Yellow solid, mp 152−153 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.04

(s, 1H), 7.95 (dd, 1H, ³J = 8.2 Hz, ⁴J = 3.1 Hz), 7.54 (td, 2H, ³J = 9.0 Hz,

⁴J = 2.2 Hz), 7.50−7.52 (m, 1H), 7.40−7.44 (m, 1H), 7.35−7.39 (m,

2H), 7.13−7.16 (m, 1H), 7.06−7.10 (m, 4H). ¹³C{¹H} NMR (126

6-Fluoro-3-(4-methoxyphenyl)-4H-chromen-4-one (5ap).

The title compound was prepared starting from photocatalyst

Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv), Na₂CO₃(212

mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-hydroxyarylena-

minone 6g (223 mg, 1.0 mmol, 1.0 equiv) and appropriate

arenesulfonyl chloride 4e (440 mg, 1.8 mmol, 1.8 equiv) and dry

CH₃CN (0.10 mmol/mL). The puriﬁcation of the dry crude performed

by column chromatography on silica gel provides the desired chromone

5ap (230 mg, 0.85 mmol, 85%).

MHz, CDCl₃) δ 111.1 (d, J_CF= 23.5 Hz), 118.6, 119.2, 120.1 (d, J_CF

=

8.9 Hz), 121.0 (d, J_CF= 26.1 Hz), 123.6, 124.2, 125.5 (d, J_CF= 7.7 Hz),

126.1, 129.8, 130.3, 152.4, 152.9, 156.7, 157.6, 159.5 (d, ¹J_CF= 247.1

Hz), 175.6. HRMS (TOF MS ES+) m/z [M + H]⁺calcd for C₂₁H₁₄O₃F

333.0930, found 333.0927.

3-(4-Ethoxyphenyl)-7-methoxy-4H-chromen-4-one (5am).

The title compound was prepared starting from photocatalyst

Ru(bpy)₃Cl₂·6H₂O (15.0 mg, 0.02 mmol, 0.02 equiv), Na₂CO₃(212

mg, 2 mmol, 2 equiv), appropriate O-alkylated ortho-hydroxyarylena-

minone 6f (235 mg, 1.0 mmol, 1.0 equiv) and appropriate arenesulfonyl

chloride 4t (397 mg, 1.8 mmol, 1.8 equiv) and dry CH₃CN (0.10

mmol/mL). The puriﬁcation of the dry crude performed by column

chromatography on silica gel provides the desired chromone 5am (243

mg, 0.82 mmol, 82%).

The ﬂash column chromatography was performed using a mixture of

hexane/ethyl acetate 7:1 to 3:1 as eluent to provide corresponding

chromone. R_f= 0.7 (Hex:EtAc 3:1).

White solid, mp 177−179 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.01

(s, 1H, 3.85 (s, 3H), 7.93 (dd, 1H, ³J = 8.3 Hz, ⁴J = 2.9 Hz), 7.48−7.51

(m, 3H), 7.40−7.42 (m, 1H), 6.98 (d, 2H, ³J = 8.7 Hz). ¹³C{¹H} NMR

(126 MHz, CDCl₃) δ 175.7, 159.7, 159.6 (d, ¹J_CF= 252.0 Hz), 152.7,

152.4, 130.1, 125.6, 124.4, 121.8 (d, J_CF= 25.6 Hz), 123.7, 120.1 (d, J_CF

= 9.0 Hz), 114.0, 111.1 (d, J_CF= 23.7 Hz), 55.3. HRMS (TOF MS ES+)

m/z [M + H]⁺calcd for C₁₆H₁₂O₃F 271.0775, found 271.0770.

The ﬂash column chromatography was performed using a mixture of

hexane/ethyl acetate 5:1 to 1:1 as eluent to provide corresponding

chromone. R_f= 0.3 (Hex:EtAc 3:1).

Yellow solid, mp 130−131 °C. ¹H NMR (500 MHz, CDCl₃) δ 8.20

(d, 1H, ³J = 8.8 Hz), 7.92 (s, 1H), 7.48 (d, 2H, ³J = 8.8 Hz), 6.98 (dd,

1H, ³J = 8.6 Hz, ⁴J = 2.5 Hz), 6.95 (d, 2H, ³J = 8.6 Hz), 7.84 (d, 1H, ⁴J =

2.5 Hz), 4.06 (q, 2H, ³J = 7.5 Hz), 3.91 (s, 3H), 1.43 (t, 3H, ³J = 7.5 Hz).

¹³C{¹H} NMR (126 MHz, CDCl₃) δ 196.3, 190.2, 175.9, 163.9, 158.9,

157.9, 152.0, 130.1, 127.8, 124.9, 124.0, 118.4, 114.4, 105.3, 100.0, 63.5,

55.8, 14.8. HRMS (TOF MS ES+) m/z [M + H]⁺calcd for C₁₈H₁₇O₄

297.1130, found 297.1127.

ASSOCIATED CONTENT

■

sı

* Supporting Information

The Supporting Information is available free of charge at

https://pubs.acs.org/doi/10.1021/acs.joc.0c02294.

1

General information, copies of H and ¹³C{¹H} NMR

spectra for all new compounds (PDF)

4913

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J. Org. Chem. 2021, 86, 4896−4916

The Journal of Organic Chemistry

pubs.acs.org/joc

Article

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AUTHOR INFORMATION

Corresponding Authors

Satenik Mkrtchyan − Laboratory of Homogeneous Catalysis

and Molecular Design at Center of Molecular and

Macromolecular Studies, Polish Academy of Sciences, PL-90-

■

́

363 Łodz, Poland; Email: sm19860214@gmail.com

Viktor O. Iaroshenko − Laboratory of Homogeneous Catalysis

and Molecular Design at Center of Molecular and

Macromolecular Studies, Polish Academy of Sciences, PL-90-

́

363 Łodz, Poland; Dipartimento di Chimica e Biologia “A.

̀

Zambelli”, Universita di Salerno, 84084 Fisciano, SA, Italy;

Department of Chemistry, University of Helsinki, 00014

Helsinki, Finland; orcid.org/0000-0002-5647-5326;

Email: iva108@gmail.com, viktori@cbmm.lodz.pl

Complete contact information is available at:

https://pubs.acs.org/10.1021/acs.joc.0c02294

Notes

The authors declare no competing ﬁnancial interest.

ACKNOWLEDGMENTS

■

This research is supported by a grant from National Science

Centre (NSC) Poland within the framework of European

Union’s Horizon 2020 research and innovation programme

under the Marie Skłodowska-Curie grant agreement No. 665778

(POLONEZ 2 grant, No. 2016/21/P/ST5/00630) obtained by

Dr. Satenik Mkrtchyan. This research project is also supported

by a grant from National Science Centre (NSC) Poland, the

SONATA 10 (No. 2015/19/D/ST5/02774) obtained by Dr.

Viktor O. Iaroshenko. Dr. Viktor O. Iaroshenko also appreciates

the funding for his Visiting Professorship from the University of

Salerno.

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Arylation of ortho-Hydroxyarylenaminones by Sulfonium Salts and Arenesulfonyl Chlorides: An Access to Isoflavones

DOI: 10.1021/acs.joc.0c02294

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