Visible-light-mediated arylation of: Ortho -hydroxyarylenaminones: Direct access to isoflavones

Article abstract of DOI:10.1039/c9cc09945j

In this work we highlight two new methods for the synthesis of isoflavones through consecutive domino arylation of ortho-hydroxyarylenaminones with in situ photogenerated aryl radicals. As precursors for aryl radicals we used aryl onium reagents such as diazonium and diaryliodonium salts. Notably, the photo-Meerwein arylation by aryl diazonium tetrafluoroborates demonstrated high efficiency in terms of yields and can be considered as a method of choice for the straightforward assembly of 3-aryl-substituted chromones. Ultimately, 26 compounds were prepared in good to excellent yields using the developed synthetic protocols.

Full text of DOI:10.1039/c9cc09945j

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Visible-light-mediated
arylation
of
ortho-
hydroxyarylenaminones: Direct access to isoflavones.
Satenik Mkrtchyana*, Viktor O. Iaroshenko.a*
Received 00th January 20xx,
Accepted 00th January 20xx
In this work we are highlighting two new methods for the synthesis of isoflavones through consecutive domino arylation of
ortho-hydroxyarylenaminones with in situ photo-generated aryl radicals. As precursors for aryl radicals we used aryl onium
reagents such as diazonium and diaryliodonium salts. Of note, the photo-Meerwein arylation by aryl diazonium
tetrafluoroborates demonstrated high efficiency in terms of yields and can be considered as a method of choice for the
straightforward assembling of 3-aryl-substituted chromones. Quintessential, utilising the developed synthetic protocols 26
compounds were prepared in good to excellent yields.
DOI: 10.1039/x0xx00000x
www.rsc.org/
Chromones are important privileged heterocycles, abundant not interest. There is a growing demand in cost-effective and efficient
only in the nature in the form of numerous natural compounds but methods enabling rapid and straightforward assembling of
have also gained wide-spread applications in life science, drug chromone framework with different substitution patterns.
discovery, food industry, and health-related domains of human life.1 Constantly growing attention and efforts are aimed at the search of
Isoflavonoids (3-arylchromones) are compounds which found new, concise and atom economic routes towards this interesting
numerous applications in medicines and food production. 2
heterocyclic system. For a long time 3-arylchromones, as well as
many other chromone-based drug-like heterocycles, were only
available from natural sources; later, however, by the limited set of
obsolete cyclisation reactions.1a, 3 Nowadays, bright spectrum of C-C
coupling protocols4 including Suzuki,5 Neghishi,6 Stille,7 employing 3-
halochromones as precursors were successfully utilised for the facile
preparation of those compounds.
3-Substituted chromones from ortho-hydroxyarylenaminones via photoredox
catalysis
O
O
BrCF2CO2Et
2.5 equiv
CF2CO2Et
Me
N
(a)
(b)
Me
Ir(ppy)3 (1 mol % ), NaOAc (2 equiv),
acetone, r.t, 24h, white LEDs (18W)
O
O
OH
Org. Lett. 2017, 19, 146-149
O
CF3
Me
N
Ph2S-CF3 OTf
2 equiv
Me
OH
O
Ir(ppy)3 (1 mol % ), NaOAc (2 equiv),
acetone, r.t, 6h, white LEDs (18W)
Org. Lett. 2017, 19, 146-149
The direct C-H functionalisation of 2,3-unsubstituted chromones was
also employed as an efficient strategy enabling the construction of
diverse 3-substituted chromones, such as 3-acyloxyl, 3-alkyl, 3-
perfluoroalkyl, 3-vinyl, 3-alkynyl, 3-chalcogenyl chromone
derevatives.8 Very recently we have communicated arylselenation of
2,3-unsubstituted chromones via Cu-catalysed direct C–H activation
protocol using elemental Se and aryl iodides, which leveraged the
corresponding 3-substituted chromones.9 Unfortunately, 3-
arylchromones, due to the innate inherent regioselectivity, cannot
be prepared by the direct C-3 C-H arylation of 2,3-unsubstituted
chromones using the range of arylation agents; instead, the 2-
arylchromones were detected as only isolable products.10 However,
due to the C-2 selectivity for the mentioned arylation protocol, the
efforts to establish alternative synthetic routes aiming at the
straightforward and concise preparation of 3-arylchromones is
nowadays one of the privileged tasks in the current field. Thus, the
chromone ring construction very often entails consecutive domino
O
O
BrCF2CO2Et
2 equiv
CF2CO2Et
Me
N
(c)
(d)
Me
OH
Ru(bpy)3Cl2, NEt3, NaHSO3
DMSO, r.t, 24h, visible light
,
O
ACS Omega, 2017, 2 (7), 3168–3174
O
O
NH4SCN
2 equiv
Me
N
SCN
Rose Bengal (1 mol%),
THF, r.t, air, 12h,
compact fluorescent lamp (14 W)
Me
OH
O
J. Org. Chem. 2019, 84, 2243-2251
This work:
BF4N2Ar
or
TfOIAr2
O
O
O
Me
(e)
N
Me
Photoredox catalysis
OH
Scheme 1. (a-d) Literature known tactics for 3-substituted
chromones based on photoredox catalysis; (e) Our concepts.
Owing to the importance of these heterocycles, works presenting
new conceptual synthesis of chromones in general and 3-
arylchromones in particular are still keep receiving an enormous
reactions
initiated
by
the
cyclisation
of
ortho-
a. Laboratory of Homogeneous Catalysis and Molecular Design Research Group at the
Center of Molecular and Macromolecular Studies, Polish Academy of Sciences,
Sienkiewicza 112, PL-90-363 Łodź, Poland. E-mail: iva108@gmail.com,
viktori@cbmm.lodz.pl
† Footnotes relating to the title and/or authors should appear here.
Electronic Supplementary Information (ESI) available: [details of any supplementary
information available should be included here]. See DOI: 10.1039/x0xx00000x
hydroxyarylenaminones triggered by numerous hard and soft
electrophiles11 as well as radicals.12 Very recently, during the
preparation of this manuscript, emerged a work which highlights the
use of the Pd-promoted oxidative C-H bond arylation of ortho-
hydroxyarylenaminones by arylboronic acids.13 The above
This journal is © The Royal Society of Chemistry 20xx
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mentioned tactics were successfully utilised to prepare myriads of hydroxyarylenaminone substrates react with photogenerated from
View Article Online
DOI: 10.1039/C9CC09945J
3-substituted chromone derivatives decorated with vast range of aryl onium salts aryl radicals (Scheme 2). The starting point of this
substituents and functional groups.
As the electrophile-triggered
study was to identify the appropriate reaction conditions for efficient
ortho- preparation varieties of 3-arylchromones following the appointed
cyclisation
of
hydroxyarylenaminones studied very well, the corresponding synthetic scenarios. For this we set two model reactions and focused
radical-mediated processes involving carbon-centred radicals are our efforts on the elaboration of the optimised reaction conditions
scarcely presented in the modern literature, to the best of our (Schemes 2a, b). The tables illustrating the general logic used for the
knowledge by four examples only, those are depicted on the reaction conditions optimisation are given in the Supporting
14
Schemes 1a-d.8d,
Of note, the methods for efficient radical Information (Tables 1S, 2S). It has been revealed that (1) photo-
arylation of ortho-hydroxyarylenaminones are scarce. Since the Meerwein arylation of ortho-hydroxyarylenaminones by aryl
application of organic radicals in contemporary synthetic organic diazonium tetrafluoroborates proceeded smoothly under the
chemistry, in particularly with the advent of photoredox catalysis in catalysis of Eosin Y I; (2) the arylation by diaryliodonium triflates
the recent years, has gained new momentum, the studies on the underwent with high efficiency being catalysed by Ru(bpy)3Cl2*6H2O
application of carbon-centred radicals in the synthesis of 3- IV.
BF4
OTf
N2
I
arylchromones are of current synthetic interest and urgent
importance.15
O
O
O
2
1.3 equiv
Me
3
1.5 equiv
Blue LED
Me
N
N
Green LED
(a)
(b)
Me
Me
EY (3 mol%), DMSO,
3h, r.t.
Ru(bpy)3Cl2*6H2O (2 mol%),
Ar, CH3CN, 4h, r.t.
18 examples
OH
OH
O
F
1.0 equiv
1.0 equiv
1
1
4
BF4 N2
O
26 examples
O
Me
2p
N
F
Scope:
(a)
Cl
Me
OPh
Cl
MeO
O
MeO
OH
Conditions from Table 1S
O
O
O
O
O
O
O
4cp
1c
Ph
Cl
O
4ar (83%a
,
79%b
)
4aj (80%a
, 74%b)
4av (81%a
)
4af (86%a
)
Ph
Me
tBu
OTf
I
O
O
O
O
F
Me
Me
Me
Me
O
O
Me
Me
F
O
O
O
O
N
F
(b)
3p
4be (92%a
, 84%b)
4bb (90%a
)
4bd (82%a
)
4bc (70%a
,
61%b
)
Me
MeO
OH
MeO
O
Conditions from Table 2S
1c
OCF3
4cp
O
O
O
O
O
Me
Me
CN
CF3
Ph
O
O
MeO
O
MeO
F
Br
Br
4ci (83%a, 77%b, 76%c
)
4ch (87%a
, 82%b)
4bg (79%a 63%b, 60%c
)
4bu (77%a
,
71%b)
HO
O
O
N
OEt
Me
F
NH
N
N
O
O
O
O
Ir
Ph
N
Br
Br
Ph
F
F
N
OMe
CO2
H
HN
I
O
III
O
O
MeO
O
Eosin Y
II
4dm (78%a, 71%b
)
4dl (80%a, 79%b
)
4db (81%a
,
73%b, 71%c
)
4cp (86%a
, 80%b, 83%c)
fac-Ir(ppy)3
Porphyrin
Ph
OMe
OMe
O
O
O
2
2
O
2
N
Cl
Cl
R
F
N
N
Ph
N
R
N
OCF3
N
N
F
O
O
O
,
N
N
N
O
N
N
N
4fa (81%a
,
75%b, 73%c
)
N
N
N
N
N
N
4fk (78%a
60%b
)
N
4dn (88%a
)
Cu
4ef (91%a
)
OMe
Ru
N
N
Ru
N
Ru
N
N
N
N
N
N
R
O
O
O
O
O
N
N
N
Cl
Cl
Cl
Cl
R
PF6
OMe
N
2Cl
V
VI
IV
2Cl
2Cl
N
NO2
Br
VII [Cu(dpp)2]PF6, R=Ph
VIII [Cu(dap)2]PF6, R=OMe
Me
4go (81%a
O
Me
4gt (69%a
O
Me
4gs (52%a
O
31%b)
Me
Ru(bpm)3Cl2*6H2
O
Ru(bpy)3Cl2*6H2
O
Ru(bpz)3Cl2*6H2
O
)
,
)
4ga (90%a, 79%b
)
OEt
O
O
O
Scheme 2. Model reactions for reaction conditions
optimization.
a Using aryldiazonium tetrafuoroborates (26 examples)
b Using diaryliodonium triflates (18 examples)
c Using diaryliodonium hexafluorophosphates (6 examples)
F
O
4hl (84%a
,
72%b
)
4hq (80%a, 63%b, 64%c
)
Gram scale synthesis on 10 mmol of appropriate ortho-hydroxyarylenaminone:
Aryl radicals can be generated by different light driven means from
vast range of substrates. For instance, in recent years diazonium
salts, diaryliodonium salts, sulfonium salts, aryl sulfonyl chlorides etc.
were intensively utilised in the photoredox radical-promoted
introduction of aryl substituents.15 In light of the known methods to
transform ortho-hydroxyarylenaminones into chromones, we had a
notion to study 3-arylchromone synthesis by the reactions between
the in situ photogenerated aryl radicals and ortho-
hydroxyarylenaminones. We surmised that this synthetic scenario (1)
is of no need of substrate prefunctionalisation, (2) uses the readily
available reagents, might visibly improve the preparation of 3-
arylchromones.
Me
OPh
OCF3
F
O
O
O
O
O
O
F
O
MeO
4ch (79%a
O
MeO
4db (74%a
, 69%b)
4cp (79%a
, 70%b, 72%c)
4av (75%a
,
67%b
O
)
,
73%b)
O
Ph
a Using aryldiazonium tetrafuoroborates (6 examples)
b Using diaryliodonium triflates (4 examples)
c Using diaryliodonium hexafluorophosphates (1 example)
F
O
F
O
4ef (77%a
)
4hq (70%a
)
Scheme 3. Product scope for the synthesised of 3-arylchromones.
As outlined in the Scheme 3a, model ortho-hydroxyarylenaminone
reacts smoothly with 4-fluorobenzenediazonium tetrafluoroborate
affording the corresponding chromone product 4cp in 86% yield
(Table 1S, Entry 4). The optimised reaction conditions for this
transformation consisted in use of 1.3 equiv. of salt 2p, Eosin Y I
photocatalyst (3 mol%), in DMSO, under the intensive irradiation
with green light (The best efficiency was observed for 24 Wat green
LED stripes), the reaction reaches its completion within 3 hours at
Herein, in continuation of our work on developing new methods for
the preparation of structurally diverse chromone derivatives with
different substitution patterns12, 16, we describe, for the first time,
two unprecedented domino cyclisation scenarios, wherein the ortho-
2 | J. Name., 2012, 00, 1-3
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room temperature under argon atmosphere. On the other hand, without photocatalysts, this led to the failure of the reactions (Table
View Article Online
DOI: 10.1039/C9CC09945J
encouragingly, the 3-arylchromone 4cp can be also prepared in 80% 1S, Entries 5, 6; Table 2S, Entries 9, 10). Second, the addition of
yield following the route of the Scheme 3b by a reaction between radical quencher such as the 2,2,6,6-tetramethyl-1-piperidinyloxy
ortho-hydroxyarylenaminone and diaryliodonium triflate 3p (1.5 (TEMPO 1.5 and 1.7 equiv. respectively) inhibited both reactions
equiv.), applying Ru(bpy)3Cl2*6H2O IV (2 mol%) as catalyst, CH3CN as through the suppressing the formation of product 4cp, most likely by
solvent within 4 hours at room temperature (Table 2S, Entry 6). For trapping most of Ar radicals (Table 1S, Entry 7; Table 2S, Entry 11).
this case the best outcome was obtained when we used 34 Wat Kessil These experiments can be accepted as an indication that
KSH150B Blue LED as a source of blue light. Furthermore, other photochemically-generated radical intermediates are indeed
tested photocatalysts depicted in the Scheme 2, like Porphyrin II and involved in both transformations.
Postulated mechanism:
fac-Ir(ppy)3 III showed catalytic activity for photo-Meerwein
Ru(bipy)2
EY
hv
hv
+ e
arylation as well. For instance, the fac-Ir(ppy)3 which under the blue
light irradiation allowed the preparation of chromone 4cp in 79%
yield by using diazonium salt and in 77% by using diaryliodonium salt
(Table 1S, Entry 10; Table 2S Entry 2). Furthermore, a range of
common Ru-based photocatalysts were tested in line with the given
transformation as well. Noteworthy, species V and VI showcased also
positive outcomes, however not as positive as complex IV did. (Table
2S, Entries 12, 13). In terms of light sources, the best yields were
observed when the strong 24 Wat and 34 Wat irradiation LED sources
of green and blue light correspondingly were used. In both cases less
powerful light sources were also tested and the model reactions
demonstrated high efficiency; however, reducing the power of the
light resulted in longer reaction duration. (This data is not presented
in the Supporting Information). On the other hand, it should be
mentioned that well-defined for such reactions cupper complexes VII
and VIII were rigorously studied as well. Unfortunately, these
catalysts experienced a failure in application to the title arylation
protocols (Table 2S, Entries 14-16).
With the inspired optimal reaction conditions for both presented
synthetic scenarios in hand, as next we decided to explore a
substrate scope and have evaluated the feasibility of the developed
synthetic protocols for the preparation of structurally diverse 3-
arylchromones. We selected eight ortho-hydroxyarylenaminones 1
which were reacted with twenty-two aryl diazonium
tetrafluoroborates 2 and sixteen diaryliodonium triflates 3. To our
delight, various diazonium tetrafluoroborates bearing diverse
functional groups including Me, Ph, OPh OMe, OEt, F, Cl, Br, CN, NO2,
CF3, and OCF3 substituents in ortho-, meta-, para- positions as well as
reagent with 1-naphthalenyl residue readily reacted with ortho-
hydroxyarylenaminones decorated by Me, OMe, OEt, F, Cl groups on
the benzene ring. Generally, this method displayed satisfactory
tolerance to both structural components affording the desired
heterocycles in moderate to high yields. Importantly, these methods
could be utilised for the preparation of 3-aryl-4H-benzo[h]chromen-
4-ones 4hl, 4hq also in excellent yields (Scheme 3). For the second
methodology involving the diaryliodonium triflates 3, we generally
+ e
Ru(bipy)3
*
*
Ru(bipy)2
EY BF4
EY
I
BF4
OTf
N2
SET
- N2
SET
- ArI
(a)
(b)
2
3
O
O
Me
N
OH
Me
N
HO
Me
1
5
Me
-e
(c)
O
O
O
O
O
H
Me
N
Me
O
H
-Me2NH2
N
Me
6
4
7
Me
Scheme 4. Proposed mechanism for the synthesis of 3-
arylchromones by photocatalytic arylation of ortho-
hydroxyarylenaminones by aryl onium salts.
Finally, according to the above illustrated results and literature on
visible-light photoredox-catalysed reactions available to date,15
a
plausible reaction mechanism for these visible-light promoted
domino cyclisation was proposed and is outlined in the Scheme 4.
Initially, under the irradiation by appropriate light source Eosin Y and
Ru(II) complex are transferred to their excited states. Under visible-
light conditions the generation of aryl radical (Ar•) from
aryldiazonium tetrafluoroborates and diaryliodonium triflates occurs
as the first step in the current mechanism sequences catalysed by
exited *Eosin Y and *Ru(II) species respectively (Schemes 4a, 4b).
Giving more details: The corresponding excited *Eosin Y species
+
undergoes the oxidative quenching by the ArN2 cation which
proceeds according to the major literature data15 via a single electron
transfer (SET) to afford the Ar•. The excited triplet state of the *Ru(II)
contains an electron located in the higher singly occupied molecular
orbital (SOMO), this electron participates in the SET event, thus
observed the slightly diminished overall yields. Furthermore, we making the excited *Ru(II) species as an one-electron reductant.
Noteworthy, the generation of Ar• by visible-light from Ar2I+ follows
the route typical for transition-metal photocatalysts.15c,e, 17 Namely,
the exited *Ru(II) donates an electron onto Ar2I+. This causes its
decomposition to ArI and the Ar•. Subsequently, the formed Ar•
undergoes prompt attack on the enaminone to afford the radical
intermediate 5 which afterwards is oxidised to carbocation 6
followed by the pyrone ring formation. Finally, after the elimination
of dimethylamine from the 2-(dimethylamino)chroman-4-one 7 the
chromone framework 4 forms. Similar type of mechanism was very
illustrated gram scale reactions for both methods to prepare
compounds 4av, 4ch, 4cp, 4db, 4ef, 4hq (Scheme 3). It is important
to mention that besides diaryliodonium triflates the corresponding
hexafluorophosphates demonstrated the ability to enter this
reaction, thus six compounds (4bg, 4ci, 4cp, 4db, 4fa, 4hq) were
prepared without significant deviations in the yields (Scheme 3).
To gain insights into the mechanism and prove that the illustrated
routes indeed involve photochemically-generated aryl radicals, the
set of control experiments were conducted. Namely, first, we run the
reactions under our optimised reaction conditions in dark, as well as
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recently proposed for the visible-light driven synthesis of 3- 4. (a) L. Klier, T. Bresser, T. A. Nigst, K. Karaghiosoff, P. Knochel, J.
View Article Online
thiocyanato and 3-polyfluoroalkyl chromones (Scheme 1a-d).14
Am. Chem. Soc. 2012, 134, 13584–13587; (b) M. L. N. Rao, V.
Venkatesh, D. N. Jadhav, Synlett 2009, 16, 2597–2600; (c) L. Liu,
Q. Wang, Z. Zhang, Q. Zhang, Z. Du, D. Xue, T. Wang, Mol.
Diversity 2014, 18, 777–785.
DOI: 10.1039/C9CC09945J
In conclusion, we have developed two instrumentally simple, concise
and facile routes to structurally diverse 3-arylchromones using photo
arylation reactions of ortho-hydroxyarylenaminones by two different
reagents, namely the aryldiazonium tetrafluoroborates and the
diaryliodonium triflates, utilising as photocatalysts Eosin Y and
Ru(bpy)3Cl2*6H2O respectively. In the practical context, these two
methods provide the desired products with good to excellent yields,
with absolute C-3 selectivity and demonstrated excellent level of
functional group tolerance. Comparing these methodologies, it is
important to admit that the photo-Meerwein arylation reaction is
more efficient esteemed by many parameters: it shows higher yields,
utilises less expensive organo photocatalyst; and last but not the
least, the aryldiazonium salts are more readily available than the
corresponding diaryliodonium salts. Preliminary mechanistic studies
indicated that the protocols described above involve free-radical
pathways. Future work that should focus on the extension of these
concepts to other sources of aryl radicals is currently in progress in
our laboratories.
5. (a) F.-X. Felpin, J. Org. Chem. 2005, 70, 8575 – 8578; (b) I. Yokoe,
Y. Sugita, Y. Shirataki, Chem. Pharm. Bull. 1989, 37, 529–530.
6. Z. Zhang, J. Qiao, D. Wang, L. Han, R. Ding, Mol. Diversity 2014,
18, 245–251.
7. D. A. Vasselin, A. D. Westwell, C. S. Matthews, T. D. Bradshaw,
M. F. G. Stevens, J. Med. Chem. 2006, 49, 3973 – 3981.
8. (a) Y. Guo, Y. Xiang, L. Wei, J.-P. Wan, Org. Lett. 2018, 20, 3971–
3974; (b) M. O. Akram, S. Bera, N. T. Patil, Chem. Commun. 2016,
52, 12306–12309; (c) D. Kim, S. Hong, Org. Lett. 2011, 13, 4466–
4469; (d) H. Xiang, Q. Zhao, Z. Tang, J. Xiao, P. Xia, C. Wang, C.
Yang, X. Chen, H. Yang, Org. Lett. 2017, 19, 146–149; (e) P. N.
Bagle, M. V. Mane, S. P. Sancheti, A. B. Gade, S. R. Shaikh, M.-H.
Baik, N. T. Patil, Org. Lett. 2019, 21, 335–399; (f) H. Xiang, C.
Yang, Org. Lett. 2014, 16, 5686–5689; (g) J.-P. Wan, Y.-J. Pan,
Chem. Commun. 2009, 2768–2770.
Conflicts of interest
There are no conflicts to declare.
9. M. Jakubczyk, S. Mkrtchyan, I. D. Madura, P. H. Marek, V. O.
Iaroshenko, RSC Adv., 2019, 9, 25368-25376.
Acknowledgments
10. (a) M. Khoobi, M. Alipour, S. Zarei, F. Jafarpour, A. Shafiee,
Chem. Commun. 2012, 48, 2985–2987; (b) H. Choi, M. Min, Q.
Peng, D. Kang, R. S. Paton, S. Hong, Chem. Sci. 2016, 7, 3900–
3909.
11. (a) L. Fu. J-P. Wan, Asian J. Org. Chem. 2019, 767-776; (b) G. P.
Mrug, N. V. Myshko, S. P. Bondarenko, V. M. Sviripa, M. S.
Frasinyuk, J. Org. Chem. 2019, 84 (11), 7138-7147.
12. S. Mkrtchyan, V. O. Iaroshenko, Eur. J. Org. Chem. 2018, 6867–
6875.
13. J-P. Wan, Z. Tu, Y. Wang, Chem. Eur. J. 2019, 25, 6907-6910.
14. (a) H. Gao, B. Hu, W. Dong, X. Gao, L. Jiang, X. Xie, Z. Zhang, ACS
Omega, 2017, 2(7), 3168–3174; (b) Y. Gao, Y. Liu, J-P. Wan, J.
Org. Chem. 2019, 84, 2243-2251.
15. (a) M. Majek, A. J. von Wangelin, Acc. Chem. Res. 2016, 49,
2316-2327; (b) J. M. R. Narayanam, C. R. J. Stephenson, Chem.
Soc. Rev., 2011, 40, 102–113; (c) N. A. Romero, D. A. Nicewicz,
Chem. Rev. 2016, 116, 10075–10166; (d) C. K. Prier, D. A. Rankic,
D. W. C. MacMillan, Chem. Rev. 2013, 113, 5322–5363; (e) I.
Ghosh, L. Marzo, A. Das, R. Shaikh, B. König, Acc. Chem. Res.
2016, 49, 1566−1577; (f) J. K. Matsui, S. B. Lang, D. R. Heitz, G.
A. Molander, ACS Catal. 2017, 7, 2563−2575.
16. (a) V. O. Iaroshenko, S. Mkrtchyan, A. Gevorgyan, T. Grigoryan,
A. Villinger, P. Langer, RCS Adv., 2015, 5, 28717–28724; (b) A.
Kotljarov, V. O. Iaroshenko, D. M. Volochnyuk, R. A. Irgashev, V.
Ya. Sosnovskikh, Synthesis 2009, 3869-3880; (c) A. Kotljarov, R.
A. Irgashev, V. O. Iaroshenko, D. V. Sevenard, V. Ya. Sosnovskikh,
Synthesis 2009, 3233-3243.
This research project is supported by a grant from National Science
Centre (NSC) Poland within the frames of European Union’s Horizon
2020 research and innovation programme under the Marie
Skłodowska-Curie grant agreement No. 665778 (POLONEZ 2 grant,
Nr. 2016/21/P/ST5/00630) obtained by Dr. Satenik Mkrtchyan.
Notes and references
1. (a) „Chromenes, Chromanones, and Chromones”, from The
Chemistry of Heterocyclic Compounds Volume 31, Gwynn P.
Ellis (Editor), ISBN: 978-0-470-18852-1, Sep 2009, 1196 pages;
(b) A. Gaspar, M. J. Matos, J. Garrido, E. Uriarte, F. Borges, Chem.
Rev. 2014, 114, 4960- 4992; (c) S. Wetzel, R. S. Bon, K. Kumar, H.
Waldmann, Angew. Chem. Int. Ed. 2011, 50, 10800-10826; (d) S.
Martens, A. Mithöfer, Phytochemistry 2005, 66, 2399-2407.
2. (a) J. W. Lampe, J. Nutr. 2003, 133, 956–964; (b) D. K. Y. Yeung,
S. W. S. Leung, Y. C. Xu, P. M. Vanhoutte, R. Y. K. Man, Eur. J.
Pharmacol. 2006, 552, 105–111; (c) A. Wagle, S. H. Seong, H. A.
Jung, J. S. Choi, Food Chem. 2019, 276, 383 – 389; (d) Y.-W. Kim,
J. C. Hackett, R. W. Brueggemeier, J. Med. Chem. 2004, 47,
4032–4040.
3. (a) A. Aitmambetov, V. P. Khilya, Chem. Nat. Compd. 1994,
30(3), 307–311; (b) V. M. Otsalyuk, T. M. Tkachuk, S. P.
Bondarenko, V. V. Chkhalo, V. P. Khilya, Chem. Nat. Compd.
1998, 34(3), 284–288; (c) V. P. Khilya, T. M. Tkachuk, L. I.
Shevchuk, Chem. Nat. Compd. 2000, 36(6), 574–578; (d) V. V.
Semenov, D. V. Tsyganov, M. N. Semenova, R. N. Chuprov-
Netochin, M. M. Raihstat, L. D. Konyushkin, P. B. Volynchuk, E. I.
Marusich, V. V. Nazarenko, S. V. Leonov, A. S. Kiselyov, J. Nat.
Prod. 2016, 79(5), 1429-1438; (e) O. A. Lozinskii, T. V. Shokol, V.
P. Khilya, Chem. Heterocycl. Compd. 2011, 47(9), 1055–1077.
17. M. K Bogdos, E. Pinard, J. A. Murphy, Beilstein J. Org.
Chem. 2018, 14, 2035–2064.
4 | J. Name., 2012, 00, 1-3
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ChemComm
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DOI: 10.1039/C9CC09945J
Journal Name
COMMUNICATION
Graphical Abstract:
Photoredox synthesis of isoflavones
O
O
Me
N
O
26 examples
Me
OH
[C-3 Selectivity]
[Readily available starting materials]
[High overall yields]
[High step- and atom-efficiency]
[Operational simplicity]
or
BF4N2Ar
TfOIAr2
Photoredox catalysis
[Practical & Scalable]
The first visible-light-promoted direct synthesis of isoflavones following the arylation of ortho-hydroxyarylenaminones by aryl onium
salts was developed.
This journal is © The Royal Society of Chemistry 20xx
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