Tandem Acceptorless Dehydrogenative Coupling-Decyanation under Nickel Catalysis

Siba P. Midya, Murugan Subaramanian, Reshma Babu, Vinita Yadav, and Ekambaram Balaraman*

Article

Tandem Acceptorless Dehydrogenative Coupling−Decyanation

under Nickel Catalysis

Cite This: J. Org. Chem. 2021, 86, 7552 −7562

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sı Supporting Information

ABSTRACT: The development of new catalytic processes based

on abundantly available starting materials by cheap metals is always

a fascinating task and marks an important transition in the

chemical industry. Herein, a nickel-catalyzed acceptorless dehy-

drogenative coupling of alcohols with nitriles followed by

decyanation of nitriles to access diversely substituted oleﬁns is

reported. This unprecedented CC bond-forming methodology takes place in a tandem manner with the formation of formamide

as a sole byproduct. The signiﬁcant advantages of this strategy are the low-cost nickel catalyst, good functional group compatibility

(

ether, thioether, halo, cyano, ester, amino, N/O/S heterocycles; 43 examples), synthetic convenience, and high reaction selectivity

and eﬃciency.

INTRODUCTION

Scheme 1. Tandem Acceptorless Dehydrogenative

Coupling−Decyanation in the Oleﬁn Synthesis

■

Oleﬁns are one of the most important organic scaﬀolds widely

found in many natural products and have been eﬀectively

utilized as fundamental building blocks in the large-scale

production of plastics and pharmaceuticals. The Wittig

reaction is the most commonly employed synthetic method-

ology for the selective synthesis of E-alkenes from carbonyl

compounds. Equally, Julia oleﬁnation, the Peterson reaction,

and Tebbe oleﬁnation are also broadly used approaches to

access the substituted oleﬁns. The classical approach to access

linear or cyclic oleﬁns is mainly based on a ruthenium-

catalyzed metathesis reaction. A signiﬁcant number of

various research groups in the use of well-deﬁned nickel

catalysts for the C−C and C−N bond formation via ADC and

transition-metal-catalyzed cross-coupling reactions have paid

much attention to the (E)-oleﬁn synthesis, including a Pd-

HA reactions. Herein, an unprecedented reactivity in the

dehydrogenative coupling of alcohols with nitriles to access

diversely substituted (E)-oleﬁns in contrast to the archetypical

α-alkylated/alkenylated products is reported. This new CC

bond-forming methodology takes place via the ADC/

decyanation tandem with the formation of formamide as the

byproduct. Notably, the removal of the cyano group from

catalyzed Heck-type coupling.

In recent times, transition-metal-catalyzed acceptorless

dehydrogenation (AD) and the hydrogen autotransfer (HA)

strategy have been widely explored for the formation of C−C

and C−N bonds using abundantly available alcohols as

8,9

feedstocks. Seminal works on ruthenium-catalyzed dehydro-

genative Wittig and Julia-type oleﬁnation of alcohol were

organic molecules is very challenging.

0a,b

reported by the research group of Milstein₁

and by others

with diﬀerent catalytic systems (Scheme 1). The same group

reported an earth-abundant manganese-catalyzed direct

condensation of alcohols into alkenes using hydrazine or

hydrazone via acceptorless dehydrogenative coupling

RESULT AND DISCUSSION

■

Initially, the reaction of 4-methoxybenzyl alcohol (1a) and 2-

phenylacetonitrile (2a) was chosen as a model system for the

Ni-catalyzed dehydrogenative coupling to form (E)-1-me-

(

ADC). Of late, transition-metal-catalyzed dehydrogenative

coupling of alcohols with nitrile to lead to α-alkylated or α-

alkenylated arylacetonitriles with the liberation of hydrogen

and/or water has been well studied via ADC and hydrogen

Received: March 12, 2021

Published: May 25, 2021

autotransfer (HA) strategies. It is noteworthy that Li and co-

workers reported a rhodium-catalyzed direct coupling of

arylacetonitriles and primary alcohols to α-alkylated arylaceta-

mides. Recent years have witnessed tremendous interest by

2021 American Chemical Society

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Table 1. Optimization Studies

entry

Ni catalyst

base

solvent

temp (°C)

yield (%) 3a/3a′

Cat. I

Cat. II

KO Bu

n-octane

toluene

135

110

135

120

100

120

64/22

52/25

27/15

42/20

20/8

33/18

87/5

48/14

trace

KO Bu

NiCl ·6H O

KO Bu

Cat. I

KO Bu

Cat. I

−

KO Bu

THF

KO Bu

1,4-dioxane

n-octane

KO Bu

Cat. I

−

Reaction conditions: alcohol 1a (1.2 mmol), nitrile 2a (1.0 mmol), Cat. [Ni] (5 mol %), KO Bu (1.0 equiv), and solvent (1.5 mL) heated at

00−135 °C (oil-bath temperature) for 24 h. Yield determined by GC using 1,4-dibromobutane as an internal standard. Reaction using 1.2 mmol

of KO Bu.

thoxy-4-styrylbenzene. After careful investigation of various

parameters, such as the use of nickel catalysts, bases, solvents,

and temperature (Table 1), the optimal reaction conditions

yields). However, p-CF -substituted benzyl alcohol did not

yield the desired product under standard reaction conditions.

This result indicates that the electronic nature of the

substituent may play an important role in the present

transformation. Thus, electron-rich meta-substituted alcohols

were reacted smoothly with 2a and yielded the corresponding

stilbenes (3k−3n) in excellent yields. It is noteworthy that the

unprotected amine group such as 3-aminobenzyl alcohol (1m)

underwent the (E)-oleﬁnation reaction selectively and gave 3m

as a sole product in 76% yield. Remarkably, both sterically

demanding ortho-substituted benzyl alcohols and multisub-

stituted benzyl alcohols were smoothly reacted with 2a and

aﬀorded the desired products 3p−3u in excellent yields (up to

92% yield). The bicyclic aromatic primary alcohols (1-naphthyl

and 2-naphthyl) proceeded eﬃciently and yielded the

corresponding (E)-alkenes in good yields (products 3v in

78% and 3w in 72% isolated yields). Notably, heteroaryl

aromatic primary alcohols were well tolerated, and the

corresponding oleﬁnic products 3x−3z were obtained in

good yields. Interestingly, 2,6-pyridinedimethanol provided

the corresponding dioleﬁnated product 3za in moderate yield.

Under our optimal reaction conditions, aliphatic alcohols (1-

hexanol and 1-decanol) selectively led to the saturated alkanes

as the major product (3zb in 52% yield and 3zc in 63% yield).

Indeed, sterically hindered secondary alcohols such as 1,1-

diarylmethanols (1zd−1ze) delivered the corresponding

trisubstituted alkene derivatives 3zd and 3ze in good yields.

However, α-methylbenzyl alcohol (1zf) and 2-pentanol (1zg)

failed to yield the corresponding oleﬁnated products 3zf (∼8%

only) and 3zg.

were determined. Reﬂuxing at 135 °C of 1a (1.2 mmol), 2a

(

1.0 mmol), and KO Bu (1.0 mmol) in n-octane in the

presence of complex I (5 mol %) gave a 64% yield of (E)-1-

methoxy-4-styrylbenzene 3a along with 22% of 1-methoxy-4-

phenethylbenzene 3a′ (Table 1, entry 1). Under similar

reaction conditions, complex II gave 3a and 3a′ in 52% and

5% yields, respectively (Table 1, entry 2). Other commer-

cially available nickel salts such as NiCl , Ni(acac) , Ni(OTf) ,

and NiCl (PMe ) gave the product 3a in poor yield (<32%;

3 2

see the SI). Other solvents such as toluene, THF, and 1,4-

dioxane were found to not be suitable for this transformation,

and the results are unsatisfactory (Table 1, entries 4−6).

Performing the reaction at 120 °C reduces the formation of 3a′

and selectively yields 87% of product 3a (Table 1, entry 7). As

the temperature is further lowered, a poor result was obtained

(

Table 1, entry 8). Decreasing the catalyst load and replacing

KO Bu with either NaO Bu or LiO Bu provided considerably

lower yields (see the SI). In control experiments performed by

employing only base and without catalyst and base, no product

formation was observed, indicating that the catalyst and base

are essential for the success of the reaction.

Having optimal reaction conditions in hand, the scope of the

various alcohols on dehydrogenative coupling with 2a to access

diverse (E)-alkenes was investigated. As shown in Table 2, a

range of electron-rich primary alcohols (p-OMe, p-Me, and p-

SMe) eﬃciently reacted with 2a under the present Ni(II)-

catalyzed conditions and aﬀorded the corresponding alkene

derivatives in excellent yields (products 3a−3c; up to 84%

yield). Electron-withdrawing halogen substituents (F-, Cl-, and

Br-) at the para position of benzyl alcohol provided the

products 3e−3g in 58%, 62%, and 63% yields, respectively. A

Next, the scope of this unprecedented catalytic dehydrogen-

ative coupling of alcohols with nitriles was explored using

various aryl nitriles (Table 3). Initially, 4-methoxybenzyl

alcohol (1a) was chosen as a benchmark substrate to show

the versatility of this transformation. Thus, the reaction of 1a

with electron-rich aryl nitriles proceeded smoothly and led to

similar result was obtained in the case of p-CN- and p-CO Me-

substituted benzyl alcohols (products 3i in 41% and 3j in 44%

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Table 2. Nickel-Catalyzed Acceptorless Dehydrogenative Coupling−Decyanation: Scope of Alcohols

Reaction conditions: alcohol 1 (1.2 mmol), nitrile 2a (1.0 mmol), Cat. I (5 mol %), KO Bu (1.2 equiv), and n-octane (1.5 mL) heated at 120 °C

(oil-bath temperature) for 24 h (isolated yields). Yield of the corresponding hydrogenated product. CH ONa was used as a base. 0.5 mmol of

a. By GC and GC-MS.

the desired products 4a in 78%, 4b in 67%, 4c in 71%, 4d in

3%, and 4f in 69% yields, respectively. To our delight, direct

synthesis of DMU-212 (4e), a drug used for breast cancer

treatment, has been achieved in excellent yield (83%). The

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Table 3. Nickel-Catalyzed Acceptorless Dehydrogenative Coupling−Decyanation: Scope of Nitriles

Reaction conditions: alcohol 1 (1.2 mmol), nitrile 2 (1.0 mmol), Cat. I (5 mol %), KO Bu (1.2 equiv), and n-octane (1.5 mL) heated at 120 °C

(oil-bath temperature) for 24 h (isolated yields). Yield of the corresponding hydrogenated product.

Scheme 2. Direct Synthesis of Resveratrol (6)

reaction of electron-deﬁcient aryl nitrile such as 2-(4-

ﬂuorophenyl)acetonitrile 2g with 4-ﬂuorobenzyl alcohol 1g

under the optimal conditions provided 4g in moderate yield.

Moreover, heterocyclic alcohol 1h with 4-methyl phenyl-

acetonitrile resulted in the corresponding trans-alkene 4h in

step-economic process to resveratrol (6), a pan-assay

interference compound (Scheme 2).

To gain insight into the reaction mechanism, several control

experiments were performed (Scheme 3). GC analysis of the

model reaction system (in the absence of 2a) indicated the

formation of the dehydrogenated product (4-methoxybenzal-

dehyde) and hydrogen gas. This result shows that the initial

step is the acceptorless dehydrogenation pathway of alcohol.

Deuterium-labeling experiments were conducted, and the

results suggest the involvement of hydrogen autotransfer

strategy in the overall process and that one of the two benzylic

C−D/H bonds of alcohol needs to be cleaved in order to

initiate the α-alkylation reaction (Scheme 3a). Reaction of

benzyl alcohol (1d) with deuterated phenyl acetonitrile [D]-2a

resulted in 52% yield of 3d without deuterium incorporation.

No deuteration in the oleﬁnic product suggests that the

benzylic hydrogen of the nitrile derivative is not taking part in

7% yield. Notably, the reaction of 1a and highly electron-

deﬁcient 3,5-bis(triﬂuoromethyl) phenylacetonitrile 2i led to

the α-alkylated nitrile product 4i in moderate yield (54%) as

the sole product.

Gratifyingly, we have successfully demonstrated the

scalability of this catalytic protocol under mild conditions. In

this regard, the present nickel-catalyzed dehydrogenative

coupling was tested for a large-scale synthesis of 3d, 3v, and

3zd (5.0 mmol scale), and it worked excellently and aﬀorded

the corresponding products in good yields. Next, we have

extended our synthetic strategy for synthesis of pharmaceuti-

cally important molecules. As a result, we have established a

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Scheme 3. Mechanistic Studies

Standard conditions: Cat. I (5 mol %), KO Bu (1.2 equiv), and n-octane (1.5 mL) heated at 120 °C (oil-bath temperature).

Scheme 4. Plausible Mechanism

the hydrogen autotransfer reaction (Scheme 3b). A control

experiment showed that phenylacetonitrile undergoes the base-

catalyzed Knoevenagel condensation with the in situ generated

aldehyde intermediate. Treatment of α-alkenylated nitrile

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mL ace pressure tube were added alcohol 1zi (1.2 mmol, 201 mg),

Article

(

7) ²^hwith benzyl alcohol (1d) resulted in 72% yield of the α-

EXPERIMENTAL SECTION

. General Information. All catalytic experiments were carried

■

alkylated nitrile (8) and 5% yield of the desired product (3d),

which suggests the involvement of the hydrogen autotransfer

step in the present catalysis. Furthermore, experiments aimed

at identifying the possible potential intermediates were

performed (Scheme 3c,d). When alcohol 1d was reacted

with nitrile 2a under standard reaction conditions for 8 h, it

resulted in a mixture of products. GC and GC-MS analyses of

this reaction mixture exhibited the formation of 1,2-diphenyl-

ethane (3d′, 2%), (E)-stilbene (3d, 17%), α-alkylated nitrile

out using standard Schlenk techniques. All solvents were reagent

grade or better. Deuterated solvents were used as received. Nickel salt

precursors were used without additional puriﬁcation. All the starting

materials (alcohols (1) and nitriles (2)) are commercially available

and were puriﬁed according to the standard procedure. The ligand

,6-bis(morpholinomethyl)pyridine and the corresponding Ni(II)

complexes (I−II) were synthesized based on the reported procedure.

Thin-layer chromatography (TLC) was performed using silica gel 60

F₂₅₄coated on an aluminum sheet purchased from Merck, which was

visualized with UV light at 254 nm or under iodine. Column

(

8, 6%), and α-alkylated amide (9, 45%). This observation

signiﬁes that α-alkylated amide and/or α-alkylated nitrile are

the potential intermediates. To gain insight into the ﬁnal

elimination step, both α-alkylated nitrile (8) and α-alkylated

chromatography was performed with SiO (SilicycleSilicaﬂash F60

(230−400 mesh)). H NMR (200, 400, or 500 MHz) and C NMR

(50, 100, or 126 MHz) spectra were recorded on the NMR

spectrometer. Deuterated chloroform was used as the solvent, and

chemical shift values (δ) are reported in parts per million relative to

12e,13

amide (9) were separately prepared

and employed in the

present nickel catalysis (Scheme 3e). This result clearly

indicates that the ﬁnal elimination step is more facile in the

case of α-alkylated amide and leads to the formation of

formamide as the sole byproduct. The control experiment also

indicates that a base-mediated E2 elimination is operative, and

nickel catalyst promotes the E2 elimination. Finally, the

hydration of 8 was examined. We believe that the hydration of

α-alkylated arylacetonitriles 8 with water, which results from

the Knoevenagel condensation step, produces the α-alkylated

the residual signals of this solvent [δ 7.27 for H (chloroform-d), δ

7.0 for C (chloroform-d)]. Abbreviations used in the NMR follow-

up experiments: br, broad; s, singlet; d, doublet; t, triplet; q, quartet;

m, multiplet. GC analysis was carried out using an HP-5 column (30

m, 0.25 mm, 0.25 μ). Mass spectra were obtained on a GCMS-QP

000 instrument with ionization voltages of 70 eV. High-resolution

mass spectra (HRMS) were obtained by fast atom bombardment

(FAB) using a double focusing magnetic sector mass spectrometer

and electron impact (EI) ionization technique (magnetic sector−

electric sector double focusing mass analyzer).

2A. General Procedure for the Ni-Catalyzed Synthesis of

E)-Stilbene. To an oven-dried 15 mL ace pressure tube were added

arylacetamide 9 suggested by Li and coworkers. When the

N −Ni(II) complex/KO Bu system was employed, the

reaction of 8 with an equimolar amount of water was

performed and yielded 9 in 74% yield (Scheme 3f).

(

alcohol 1 (1.2 mmol), nitrile 2 (1.0 mmol), Ni-complex I (5 mol %,

1 mg), and KO Bu (1.2 mmol, 134 mg) in n-octane (1.5 mL) under

Based on the mechanistic studies and our previous works, a

plausible mechanism for the N,N,N-nickel(II)-catalyzed

tandem acceptorless dehydrogenative coupling−decyanation

in the oleﬁn synthesis is depicted in Scheme 4. Initially, in the

a gentle stream of argon. The mixture was heated at 120 °C (oil-bath

temperature) for 24 h followed by cooling to room temperature. The

reaction mixture was diluted with water (4 mL) and extracted with

dichloromethane (3 × 5 mL). The resultant organic layer was dried

over anhydrous Na SO , and the solvent was evaporated under

reduced pressure. The crude mixture was puriﬁed by silica gel column

chromatography (230−400 mesh size) using petroleum-ether/ethyl

acetate as an eluting system.

presence of alcohol and base, the N,N,N-Ni(II)Cl complex I

undergoes a displacement reaction with chloride ligand to give

complex III. The complex III undergoes β-hydride elimination

(

of alkoxide) to lead to the corresponding aldehyde and with

B. Large-Scale Synthesis of 3d, 3v, and 3zd. To an oven-

the formation of Ni−H species IV. The complex VI was

generated from complex V with the liberation of H . Finally,

dried 35 mL ace pressure tube were added alcohol 1d or 1v or 1zd

(5.5 mmol), nitrile 2 (5.0 mmol), Ni-complex I (5 mol %, 105 mg),

the complex VI reacts with alcohol to regenerate the catalyst I.

Followed by the initial dehydrogenation of alcohol under Ni

catalysis, the in situ generated aldehyde undergoes the

Knoevenagel condensation with nitrile and led to vinyl nitrile

and KO Bu (5.5 mmol, 616 mg) in n-octane (8 mL) under a gentle

stream of argon. The mixture was heated at 120 °C (oil-bath

temperature) for 36 h followed by cooling to room temperature. The

reaction mixture was diluted with water (15 mL) and extracted with

dichloromethane (3 × 10 mL). The resultant organic layer was dried

over anhydrous Na SO , and the solvent was evaporated under

(7) by the elimination of a water molecule. Next, the α-

alkenylated intermediate 7 undergoes catalytic (transfer)-

hydrogenation to lead to the α-alkylated product 8 by in situ

generated hydrogen from the initial dehydrogenation of

alcohol. Finally, intermediate 8 undergoes hydrolysis (by

water resulting from the α-alkenylation step) to produce α-

alkylated arylacetamide (9). Subsequent elimination of

formamide from 9 eventually delivers the product (E)-stilbene.

The formation of saturated alkanes was observed in the case of

aliphatic alcohols due to the further hydrogenation (double

HA) of the corresponding oleﬁnated product.

reduced pressure. The crude mixture was puriﬁed by silica gel column

chromatography (230−400 mesh size) using petroleum-ether/ethyl

acetate as an eluting system and yielded the desired products 3d, 3v,

and 3zd in 68% (612 mg), 80% (920 mg), and 87% (1.11 g) yields,

respectively.

2C. Two-Step synthesis of Resveratrol. To an oven-dried 15

CONCLUSION

■

nitrile 2b (1.0 mmol, 147 mg), Ni-complex I (5 mol %, 21 mg), and

In summary, we have disclosed an unprecedented tandem

acceptorless dehydrogenative coupling−decyanation in the

oleﬁn synthesis. This new CC bond forming methodology is

catalyzed by nickel and aﬀords diversely substituted (E)-oleﬁns

KO Bu (1.2 mmol, 134 mg) in n-octane (1.5 mL) under a gentle

stream of argon. The mixture was of heated at 120 °C for 24 h

followed by cooling to room temperature. The reaction mixture was

diluted with water (4 mL) and extracted with dichloromethane (3 × 5

mL). The resultant organic layer was dried over anhydrous Na SO ,

and the solvent was evaporated under reduced pressure. The crude

mixture was puriﬁed by silica gel column chromatography (230−400

mesh size) using petroleum-ether/ethyl acetate as an eluting system.

(

43 examples; up to 92% yield) with the formation of

formamide as the only byproduct. Several control and labeling

experiments provide the basis for our assertion that the

reaction proceeds via the borrowing hydrogenation.

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The Journal of Organic Chemistry

J. Org. Chem. 2021, 86, 7552−7562

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s, 2H). ¹³C NMR{ H} (50 MHz, chloroform-d) δ = 136.9, 136.1,

(

28.9, 128.8, 128.6, 127.6, 126.5.

E)-1-Bromo-4-styrylbenzene (3g).

synthesized according to the general procedure described in section

(

The title compound was

A. The product was puriﬁed using silica gel (230−400 mesh)

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 63%, 154 mg. H NMR (200 MHz,

chloroform-d) δ = 7.65−7.49 (m, 4H), 7.49−7.30 (m, 6H), 7.11 (d, J

To a 15 mL clean, oven-dried screw cap reaction tube were added

(0.5 mmol, 135 mg) and samarium(II) iodide (THF solution, 8

3.7 Hz, 2H). C NMR{ H} (50 MHz, chloroform-d) δ = 136.9,

36.3, 131.8, 129.4, 128.7, 127.9, 127.9, 127.4, 126.5, 121.3.

equiv, 1.6 g) followed by Et N (72 equiv, 0.5 mL) and H O (72

18b

(

E)-4-Styryl-1,1′-biphenyl (3h).

The title compound was

equiv, 0.65 mL) under argon atmosphere, resulting in the formation

synthesized according to the general procedure described in section

of a dark brown color of the SmI −Et N−H O complex. Then the

A. The product was puriﬁed using silica gel (230−400 mesh)

reaction mixture was stirred for 24 h at room temperature. After the

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 70%, 179 mg. H NMR (200 MHz,

completion of reaction, the reaction mixture was diluted with CH Cl

and NaOH (1 N) solution. The aqueous layer was extracted with

chloroform-d) δ = 7.58−7.18 (m, 14H), 7.08 (s, 2H). C NMR{ H}

50 MHz, chloroform-d) δ = 140.7, 140.3, 137.3, 136.4, 128.8, 128.7,

28.2, 127.6, 127.3, 126.9, 126.5.

CH Cl (3 × 30 mL), and the combined organic layers were dried

(

over Na SO and concentrated. The crude mixture was puriﬁed by

silica gel column chromatography (230−400 mesh size) using

(E)-4-Styrylbenzonitrile (3i).

The title compound was synthe-

CH Cl /MeOH as an eluting system.

sized according to the general procedure described in section 2A. The

product was puriﬁed using silica gel (230−400 mesh) column

chromatography using a mixture of petroleum ether/EtOAc as an

. Characterization Data of Compounds. (E)-1-Methoxy-4-

18a

styrylbenzene (3a).

The title compound was synthesized

according to the general procedure described in section 2A. The

product was puriﬁed using silica gel (230−400 mesh) column

chromatography using a mixture of petroleum ether/EtOAc as an

eluent. White solid. Yield: 41%, 84 mg. H NMR (200 MHz,

chloroform-d) δ 7.59−7.44 (m, 6H), 7.35−7.24 (m, 3H), 7.15 (d, J =

4.7 Hz, 1H), 7.00 (d, J = 16.2 Hz, 1H). C NMR{ H} (50 MHz,

eluent. White solid. Yield: 84%, 176 mg. H NMR (200 MHz,

chloroform-d) δ = 141.8, 136.2, 132.4, 128.8, 128.6, 126.9, 126.8,

26.7, 118.9, 110.5.

E)-Methyl 4-styrylbenzoate (3j).

synthesized according to the general procedure described in section

chloroform-d) δ = 7.51−7.44 (m, 4H), 7.35 (t, J = 7.0 Hz, 2H), 7.27−

(

.23 (m, 1H), 7.02 (d, J = 7.4 Hz, 2H), 6.90 (d, J = 9.1 Hz, 2H), 3.83

s, 3H). ¹³C{ H} NMR (50 MHz, CHLOROFORM-d) δ = 159.2,

(

The title compound was

37.6, 130.1, 128.6, 128.1, 127.7, 127.1, 126.6, 126.2, 114.1, 55.3.

A. The product was puriﬁed using silica gel (230−400 mesh)

(E)-1-Methyl-4-styrylbenzene (3b).

The title compound was

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 44%, 104 mg. H NMR (500 MHz,

synthesized according to the general procedure described in section

A. The product was puriﬁed using silica gel (230−400 mesh)

chloroform-d) δ = 7.95 (d, J = 8.3 Hz, 2H), 7.49−7.45 (m, 4H),

column chromatography using a mixture of petroleum ether/EtOAc

.31−7.28 (t, J = 7.6 Hz, 2H), 7.23−7.20 (m, 1H), 7.13 (d, J = 16.4

as an eluent. White solid. Yield: 72%, 139.7 mg. H NMR (200 MHz,

13 1

chloroform-d) δ = 7.42 (d, J = 7.7 Hz, 2H), 7.37−7.28 (m, 3H),

Hz, 1H), 7.04 (d, J = 16.4 Hz, 1H), 3.84 (s, 3H). C NMR{ H} (126

MHz, chloroform-d) δ = 166.9, 141.8, 136.7, 131.2, 130.0, 128.9,

128.7, 128.2, 127.5, 126.7, 126.3, 52.0.

(E)-1-Methoxy-3-styrylbenzene (3k). The title compound was

synthesized according to the general procedure described in section

2A. The product was puriﬁed using silica gel (230−400 mesh)

column chromatography using a mixture of petroleum ether/EtOAc

.24−7.17 (m, 2H), 7.10 (d, J = 6.8 Hz, 2H), 7.01 (s, 2H), 2.29 (s,

H). ¹³C NMR{ H} (101 MHz, chloroform-d) δ = 137.5, 134.5,

29.4, 128.7, 128.6, 127.7, 127.4, 126.4, 21.2.

(E)-Methyl-(4-styrylphenyl)sulfane (3c).

The title compound

was synthesized according to the general procedure described in

section 2A. The product was puriﬁed using silica gel (230−400 mesh)

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 83%, 174 mg. H NMR (200 MHz,

as an eluent. White solid. Yield: 79%, 178.5 mg. H NMR (200 MHz,

chloroform-d) δ = 7.52 (d, J = 8.9 Hz, 2H), 7.37 (t, J = 7.8 Hz, 2H),

7.29−7.24 (m, 2H), 7.14−7.06 (m, 4H), 6.83 (d, J = 7.8 Hz, 1H),

chloroform-d) δ = 7.52−7.46 (m, 3H), 7.42−7.32 (m, 3H), 7.27−

.22 (m, 3H), 7.06 (s, 2H), 2.50 (s, 3H). C NMR{ H} (50 MHz,

3.85 (s, 3H). C NMR{ H} (50 MHz, chloroform-d) δ = 159.9,

chloroform-d) δ = 137.8, 137.3, 134.3, 128.6, 128.0, 127.5, 126.8,

26.6, 126.3, 15.7.

E)-1,2-Diphenylethene (3d).

138.8, 137.2, 129.6, 128.9, 128.6, 128.5, 127.6, 126.5, 119.2, 113.3,

111.7, 55.2.

(E)-1-Methyl-3-styrylbenzene (3l).

18c

(

The title compound was synthe-

The title compound was

sized according to the general procedure described in section 2A. The

product was puriﬁed using silica gel (230−400 mesh) column

chromatography using a mixture of petroleum ether/EtOAc as an

synthesized according to the general procedure described in section

2A. The product was puriﬁed using silica gel (230−400 mesh)

column chromatography using a mixture of petroleum ether/EtOAc

eluent. White solid. Yield: 71%, 127.8 mg. H NMR (200 MHz,

as an eluent. White solid. Yield: 75%, 145 mg. H NMR (200 MHz,

chloroform-d) δ = 7.52 (d, J = 7.1 Hz, 4H), 7.36 (t, J = 8.3 Hz, 4H),

chloroform-d) δ = 7.41 (d, J = 7.7 Hz, 2H), 7.28−7.20 (m, 4H),

.29−7.25 (m, 2H), 7.11 (s, 2H). C NMR{ H} (50 MHz,

7.18−7.10 (m, 3H), 6.99 (s, 2H), 2.27 (s, 3H). C NMR{ H} (50

MHz, chloroform-d) δ = 138.1, 137.4, 137.2, 128.7, 128.6, 128.5,

128.4, 127.5, 127.2, 126.4, 123.7, 21.4.

chloroform-d) δ = 137.3, 128.7, 128.5, 128.4, 127.6, 126.5.

(E)-1-Fluoro-4-styrylbenzene (3e).

The title compound was

synthesized according to the general procedure described in section

(E)-3-Styrylaniline (3m).

The title compound was synthesized

A. The product was puriﬁed using silica gel (230−400 mesh)

according to the general procedure described in section 2A. The

product was puriﬁed using silica gel (230−400 mesh) column

chromatography using a mixture of petroleum ether/EtOAc as an

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 58%, 115 mg. H NMR (200 MHz,

chloroform-d) δ = 7.52−7.44 (m, 4H), 7.39−7.35 (m, 1H), 7.33−

eluent. Brown solid. Yield: 76%, 148 mg. H NMR (200 MHz,

.29 (m, 2H), 7.09−7.00 (m, 4H). C NMR{ H} (50 MHz,

chloroform-d) δ = 7.43 (d, J = 9.4 Hz, 2H), 7.28 (t, J = 6.2 Hz, 2H),

7.19 (d, J = 6.2 Hz, 1H), 7.06 (d, J = 6.2 Hz, 1H), 6.97 (s, 2H), 6.86

(d, J = 9.4 Hz, 1H), 6.78 (s, 1H), 6.54 (d, J = 8.6 Hz, 1H), 3.61 (s,

chloroform-d) δ = 164.8, 159.9, 137.2, 133.4, 128.7, 128.1, 127.9,

27.6, 127.4, 126.4, 115.8, 115.4.

E)-1-Chloro-4-styrylbenzene (3f).

synthesized according to the general procedure described in section

(

The title compound was

2H). C NMR{ H} (50 MHz, chloroform-d) δ = 146.6, 138.4, 137.4,

129.6, 128.8, 128.6, 128.5, 127.5, 126.5, 117.3, 114.7, 112.9.

A. The product was puriﬁed using silica gel (230−400 mesh)

(E)-N-Methyl-3-styrylaniline (3n).

The title compound was

column chromatography using a mixture of petroleum ether/EtOAc

synthesized according to the general procedure described in section

2A. The product was puriﬁed using silica gel (230−400 mesh)

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 62%, 132 mg. H NMR (200 MHz,

chloroform-d) δ = 7.52 (d, J = 8.7 Hz, 4H), 7.41−7.30 (m, 5H), 7.12

558

J. Org. Chem. 2021, 86, 7552−7562

The Journal of Organic Chemistry

Article

as an eluent. White solid. Yield: 86%, 179 mg. H NMR (200 MHz,

(50 MHz, chloroform-d) δ = 153.4, 138.0, 137.2, 133.1, 128.7, 128.2,

chloroform-d) δ = 7.50 (d, J = 7.4 Hz, 2H), 7.35 (t, J = 8.3 Hz, 2H),

127.6, 126.4, 103.6, 61.0, 56.1.

(E)-1-Styrylnaphthalene (3v).

7.25 (d, J = 8.3 Hz, 1H), 7.18 (t, J = 8.0 Hz, 1H), 7.06 (s, 2H), 6.89

The title compound was

(

d, J = 7.1 Hz, 1H), 6.74 (s, 1H), 6.53 (d, J = 6.6 Hz, 1H), 2.86 (s,

synthesized according to the general procedure described in section

2A. The product was puriﬁed using silica gel (230−400 mesh)

column chromatography using a mixture of petroleum ether/EtOAc

H). ¹³C NMR{ H} (50 MHz, chloroform-d) δ = 148.8, 138.3, 137.4,

29.5, 129.1, 128.6, 128.5, 127.5, 126.5, 116.6, 112.7, 110.8, 31.2.

(E)-1-Chloro-3-styrylbenzene (3o).

The title compound was

as an eluent. White solid. Yield: 78%, 179 mg. H NMR (200 MHz,

synthesized according to the general procedure described in section

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 57%, 112.5 mg. H NMR (200 MHz,

chloroform-d) δ = 7.53−7.49 (m, 3H), 7.40−7.20 (m, 6H), 7.12 (d, J

chloroform-d) δ = 8.15 (d, J = 8.0 Hz, 1H), 7.83−7.67 (m, 4H),

A. The product was puriﬁed using silica gel (230−400 mesh)

7.55−7.41 (m, 4H), 7.33 (t, J = 7.6 Hz, 2H), 7.28−7.22 (m, 1H),

7.18−7.01 (m, 2H). C NMR{ H} (126 MHz, chloroform-d) δ =

137.6, 135.0, 133.7, 131.7, 131.4, 129.0, 128.7, 128.6, 128.0, 127.8,

26.7, 126.1, 125.8, 125.7, 123.8, 123.6.

10e

(

E)-2-Styrylnaphthalene (3w).

The title compound was

16.2 Hz, 1H), 7.01 (d, J = 16.4 Hz, 1H). C NMR{ H} (50 MHz,

synthesized according to the general procedure described in section

chloroform-d) δ = 139.2, 136.8, 134.6, 130.1, 129.7, 128.7, 128.0,

27.5, 127.2, 126.6, 126.3, 124.7.

E)-1-Methoxy-2-styrylbenzene (3p). The title compound was

synthesized according to the general procedure described in section

A. The product was puriﬁed using silica gel (230−400 mesh)

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 72%, 165.5 mg. H NMR (200 MHz,

(

chloroform-d) δ = 7.77−7.68 (m, 5H), 7.48 (d, J = 8.8 Hz, 2H),

A. The product was puriﬁed using silica gel (230−400 mesh)

.41−7.35 (m, 2H), 7.28 (d, J = 2H), 7.24−7.17 (m, 3H).

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 69%, 145 mg. H NMR (200 MHz,

NMR{ H} (50 MHz, chloroform-d) δ = 137.37, 134.8, 133.7, 133.0,

29.0, 128.8, 128.7, 128.3, 127.9, 127.7, 126.6, 126.5, 126.3, 125.9,

23.5.

(E)-2-Styrylpyridine (3x). The title compound was synthesized

chloroform-d) δ = 7.54−7.38 (m, 4H), 7.27 (t, J = 7.2 Hz, 2H), 7.20−

.12 (m, 2H), 7.03 (d, J = 15.5 Hz, 1H), 6.93−6.80 (m, 2H), 3.80 (s,

_H₎_.₁3C NMR{1H} (50 MHz, chloroform-d) δ = 156.9, 137.9, 129.1,

according to the general procedure described in section 2A. The

product was puriﬁed using silica gel (230−400 mesh) column

chromatography using a mixture of petroleum ether/EtOAc as an

28.6, 128.6, 127.3, 126.5, 126.4, 123.5, 120.7, 110.9, 55.5.

(E)-1-Methyl-2-styrylbenzene (3q).

The title compound was

synthesized according to the general procedure described in section

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 62%, 120 mg. H NMR (200 MHz,

eluent. Light brown solid. Yield: 58%, 105 mg. H NMR (400 MHz,

A. The product was puriﬁed using silica gel (230−400 mesh)

chloroform-d): δ = 8.59−8.61 (m, 1H), 7.61−7.68 (m, 2H), 7.57−

7.60 (m, 2H), 7.36−7.39 (m, 3H), 7.27−7.32 (m, 1H), 7.13−7.19

(

m, 2H). C NMR{ H} (100 MHz, chloroform-d): δ = 155.7, 149.8,

chloroform-d) δ = 7.61−7.51 (m, 3H), 7.37 (t, J = 6.1 Hz, 2H), 7.31−

36.7, 136.7, 132.8, 128.8, 128.4, 128.0, 127.2, 122.2.

.25 (m, 2H), 7.21−7.14 (m, 3H), 7.00 (d, J = 16.6 Hz, 1H), 2.43 (s,

10e

_H₎_.₁3C NMR{1H} (50 MHz, chloroform-d) δ = 136.5, 135.8, 130.4,

(E)-2-Styrylfuran (3y).

The title compound was synthesized

according to the general procedure described in section 2A. The

product was puriﬁed using silica gel (230−400 mesh) column

chromatography using a mixture of petroleum ether/EtOAc as an

29.9, 128.6, 127.6, 126.5, 126.2, 125.3, 19.9.

(

E)-1,3-Dimethyl-5-styrylbenzene (3r). The title compound was

synthesized according to the general procedure described in section

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 68%, 141 mg. H NMR (200 MHz,

chloroform-d) δ = 7.51 (d, J = 7.7 Hz, 2H), 7.35 (t, J = 7.1 Hz, 2H),

eluent. White solid. Yield: 61%, 103.5 mg. H NMR (200 MHz,

A. The product was puriﬁed using silica gel (230−400 mesh)

chloroform-d) δ = 7.51 (d, J = 7.3 Hz, 2H), 7.50−7.43 (m, 3H), 7.30

(

d, J = 7.3 Hz, 1H), 7.09 (d, J = 15.9 Hz, 1H), 6.95 (d, J = 16.5 Hz,

H), 6.59−6.43 (m, 1H), 6.40 (d, J = 3.1 Hz, 1H). C NMR{ H}

100 MHz, chloroform-d) δ = 153.3, 142.1, 137.0, 128.7, 127.6, 127.1,

26.3, 116.5, 111.6, 108.5.

E)-2-Styrylthiophene (3z). The title compound was synthesized

.28−7.22 (m, 1H), 7.19−7.14 (m, 2H), 7.07 (s, 2H), 6.88 (d, J =

13 1

4.8 Hz, 1H), 2.34 (s, 6H). C NMR{ H} (50 MHz, chloroform-d)

10e

(

δ = 138.1, 129.5, 128.8, 128.6, 128.3, 127.4, 126.4, 124.4, 21.3.

according to the general procedure described in section 2A. The

product was puriﬁed using silica gel (230−400 mesh) column

chromatography using a mixture of petroleum ether/EtOAc as an

(E)-1,2-Dimethoxy-4-styrylbenzene (3s).

The title compound

was synthesized according to the general procedure described in

section 2A. The product was puriﬁed using silica gel (230−400 mesh)

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 89%, 213.6 mg. H NMR (400 MHz,

chloroform-d) δ = 7.52 (d, J = 7.6 Hz, 2H), 7.37 (t, J = 8.0 Hz, 2H),

eluent. Yellow solid. Yield: 53%, 98.5 mg. H NMR (200 MHz,

chloroform-d) δ = 7.51−7.46 (m, 2H), 7.39−7.29 (m, 3H), 7.26−

.19 (m, 2H), 7.08 (d, J = 2.9 Hz, 1H), 7.04−7.00 (m, 1H), 6.94 (d, J

13 1

16.2 Hz, 1H). C NMR{ H} (50 MHz, chloroform-d) δ 142.9,

.31−7.21 (m, 1H), 7.13−7.05 (m, 3H), 7.04−6.95 (m, 1H), 6.88 (d,

36.9, 128.7, 128.3, 127.6, 126.3, 126.1, 124.3, 121.8.

13 1

J = 8.4 Hz, 1H), 3.97 (s, 3H), 3.92 (s, 3H). C NMR{ H} (100

MHz, chloroform-d) δ = 149.0, 148.9, 137.5, 130.4, 128.6, 128.4,

18e

,6-Distyrylpyridine (3za). The title compound was synthesized

according to the general procedure described in section 2A. The

product was puriﬁed using silica gel (230−400 mesh) column

chromatography using a mixture of petroleum ether/EtOAc as an

27.2, 126.7, 126.2, 119.8, 111.1, 108.7, 55.9, 55.8.

10e

(

E)-5-Styrylbenzo[d][1,3]dioxole (3t). The title compound was

synthesized according to the general procedure described in section

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. Yellowish solid. Yield: 90%, 201.6 mg. H NMR (200

eluent. White solid. Yield: 49%, 138.7 mg. H NMR (400 MHz,

A. The product was puriﬁed using silica gel (230−400 mesh)

chloroform-d) δ = 7.71 (d, J = 15.6 Hz, 2H), 7.65 (t, J = 7.8 Hz, 1H),

.62 (d, J = 7.8 Hz, 3H), 7.39 (t, J = 7.8 Hz, 4H), 7.32−7.26 (m, 5H),

13 1

.22 (d, J = 16.1 Hz, 2H). C NMR{ H} (100 MHz, chloroform-d) δ

155.4, 136.9, 136.8, 132.9, 128.7, 128.3, 128.3, 127.1, 120.4.

MHz, chloroform-d) δ = 7.50−7.46 (m, 2H), 7.34−7.25 (m, 3H),

.07 (d, J = 1.6 Hz, 1H), 7.00−6.93 (m, 3H), 6.80 (d, J = 8.0 Hz,

Heptylbenzene (3zb).

The title compound was synthesized

H), 5.97 (s, 2H). C NMR{ H} (50 MHz, chloroform-d) δ = 148.1,

47.3, 137.4, 131.9, 128.6, 128.3, 127.3, 127.0, 126.3, 121.5, 108.4,

05.5, 101.1.

according to the general procedure described in section 2A. The

product was puriﬁed using silica gel (230−400 mesh) column

chromatography using a mixture of petroleum ether/EtOAc as an

(

E)-1,2,3-Trimethoxy-5-styrylbenzene (3u).

The title com-

eluent. Sticky liquid. Yield: 52%, 91.5 mg. H NMR (200 MHz,

pound was synthesized according to the general procedure described

in section 2A. The product was puriﬁed using silica gel (230−400

mesh) column chromatography using a mixture of petroleum ether/

chloroform-d) δ = 7.26−7.09 (m, 5H), 2.53 (d, J = 6.2 Hz, 2H),

1.56−1.50 (m, 2H), 1.28−1.20 (m, 8H), 0.81 (t, J = 6.2 Hz, 3H).

NMR{ H} (50 MHz, chloroform-d) δ = 142.9, 128.4, 128.2, 125.9,

EtOAc as an eluent. White solid. Yield: 92%, 248 mg. H NMR (200

125.5, 36.0, 31.9, 31.5, 29.6, 29.5, 29.3, 22.7, 14.1.

MHz, chloroform-d) δ = 7.45−7.56 (m, 2H), 7.24−7.42 (m, 3H),

Undecylbenzene (3zc). The title compound was synthesized

.02 (s, 2H), 6.74 (s, 2H), 3.92 (s, 6H), 3.87 (s, 3H). C NMR{ H}

according to the general procedure described in section 2A. The

559

J. Org. Chem. 2021, 86, 7552−7562

The Journal of Organic Chemistry

https://pubs.acs.org/doi/10.1021/acs.joc.1c00592.

Article

product was puriﬁed using silica gel (230−400 mesh) column

chromatography using a mixture of petroleum ether/EtOAc as an

eluent. Sticky liquid. Yield: 63%, 144 mg. H NMR (200 MHz,

eluent. White solid. Yield: 69%, 143.5 mg. H NMR (200 MHz,

chloroform-d) δ = 7.24−7.08 (m, 5H), 2.52 (t, J = 6.9 Hz, 2H), 1.56−

chloroform-d) δ = 7.50 (d, J = 8.1 Hz, 4H), 7.23 (s, 4H), 7.13 (s,

2H), 2.45 (s, 6H). C NMR{ H} (50 MHz, chloroform-d) δ = 137.2,

.50 (m, 2H), 1.22−1.16 (m, 16H), 0.81 (t, J = 4 Hz, 3H).

Ethene-1,1,2-triyltribenzene (3zd).

The title compound was

134.7, 129.3, 127.6, 126.3, 21.2.

(E)-1,2-Bis(4-ﬂuorophenyl)ethane (4g).

synthesized according to the general procedure described in section

The title compound

A. The product was puriﬁed using silica gel (230−400 mesh)

was synthesized according to the general procedure described in

section 2A. The product was puriﬁed using silica gel (230−400 mesh)

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 81%, 207 mg. H NMR (200 MHz,

chloroform-d) δ = 7.32−7.29 (m, 8H), 7.23−7.18 (m, 2H), 7.11 (t, J

as an eluent. White solid. Yield: 61%, 132 mg. H NMR (200 MHz,

5.5 Hz, 3H), 7.05−7.00 (m, 2H), 6.96 (s, 1H). C NMR{ H} (50

chloroform-d) δ = 7.51−7.44 (m, 4H), 7.11−7.02 (m, 4H), 6.99 (s,

MHz, chloroform-d) δ = 143.4, 142.6, 140.3, 137.4, 130.4, 129.5,

28.6, 128.2, 127.9, 127.6, 127.5, 127.4, 126.7.

2H). C NMR{ H} (50 MHz, chloroform-d) δ = 164.8, 159.9, 133.4,

127.9, 127.8, 127.3, 115.8, 115.4.

(E)-2-(4-Methylstyryl)quinoline (4h).

18k

,4′-(2-Phenylethene-1,1-diyl)bis(methoxybenzene) (3ze). The

The title compound was

title compound was synthesized according to the general procedure

described in section 2A. The product was puriﬁed using silica gel

synthesized according to the general procedure described in section

2A. The product was puriﬁed using silica gel (230−400 mesh)

column chromatography using a mixture of petroleum ether/EtOAc

(

230−400 mesh) column chromatography using a mixture of

petroleum ether/EtOAc as an eluent. White solid. Yield: 82%, 259

as an eluent. Brown solid. Yield: 57%, 139.5 mg. H NMR (500 MHz,

mg. H NMR (200 MHz, chloroform-d) δ = 7.33−7.27 (m, 3H), 7.09

chloroform-d) δ = 8.14 (d, J = 8.5 Hz, 1H), 8.08 (d, J = 8.5 Hz, 1H),

7.79 (d, J = 8.0 Hz, 1H), 7.71−7.65 (m, 3H), 7.56 (d, J = 8.0 Hz,

2H), 7.50 (t, J = 7.6 Hz, 1H), 7.38 (d, J = 16.3 Hz, 1H), 7.22 (d, J =

(

d, J = 8.8 Hz, 6H), 6.87−6.80 (m, 5H), 3.78 (s, 6H). C NMR{ H}

50 MHz, chloroform-d) δ = 157.9, 133.7, 131.6, 129.7, 129.2, 128.8,

128.5, 127.9, 127.0, 113.8, 55.2.

7.5 Hz, 2H), 2.40 (s, 3H). C NMR{ H} (125 MHz, chloroform-d)

δ 156.1, 148.2, 138.7, 136.3, 134.4, 133.7, 129.7, 129.5, 129.1, 127.9,

127.5, 127.2, 126.0, 119.1, 21.3.

(

E)-1,2-Bis(4-methoxyphenyl)ethene (4a). The title compound

was synthesized according to the general procedure described in

section 2A. The product was puriﬁed using silica gel (230−400 mesh)

column chromatography using a mixture of petroleum ether/EtOAc

as an eluent. White solid. Yield: 78%, 187 mg. H NMR (200 MHz,

chloroform-d) δ = 7.44 (d, J = 9.1 Hz, 4H), 6.94 (s, 2H), 6.90 (d, J =

(S)-2-(3,5-Bis(triﬂuoromethyl)phenyl)-3-(4-methoxyphenyl)-

propanenitrile (4i). The title compound was synthesized according to

the general procedure described in section 2A. The product was

puriﬁed using silica gel (230−400 mesh) column chromatography

using a mixture of petroleum ether/EtOAc as an eluent. White solid.

.1 Hz, 4H), 3.84 (s, 6H). C NMR{ H} (50 MHz, chloroform-d) δ

159.0, 130.5, 127.4, 126.2, 114.1, 55.3.

E)-1-Methoxy-4-(4-methylstyryl)benzene (4b). The title com-

Yield: 54%, 201 mg. H NMR (200 MHz, chloroform-d) δ = 7.86 (s,

(

1H), 7.62 (s, 2H), 6.99 (d, J = 8.3 Hz, 2H), 6.83 (d, J = 8.3 Hz, 2H),

pound was synthesized according to the general procedure described

in section 2A. The product was puriﬁed using silica gel (230−400

mesh) column chromatography using a mixture of petroleum ether/

EtOAc as an eluent. White solid. Yield: 67%, 150 mg. H NMR (200

MHz, chloroform-d) δ = 7.45 (d, J = 9 Hz, 2H), 7.40 (d, J = 8.3 Hz,

4.12 (t, J = 6.9 Hz, 1H), 3.79 (s, 3H), 3.26−3.05 (m, 2H).

NMR{ H} (50 MHz, chloroform-d) δ = 159.3, 137.6, 132.7, 130.3,

27.9, 126.6, 122.3, 118.9, 114.2, 55.2, 41.0, 39.6. HRMS (ESI) m/z:

[M + H] Calcd for C H F NO 374.0974. Found: 374.0908.

18 14 6

(

E)-1,3-Dimethoxy-5-(4-methoxystyryl)benzene (5).

White

solid. Yield: 93%, 251 mg. H NMR (200 MHz, chloroform-d) δ =

2H), 7.17 (d, J = 7.1 Hz, 2H), 7.01 (s, 1H), 6.99 (s, 1H), 6.91 (d, J =

Hz, 2H). ¹³C NMR{ H} (50 MHz, chloroform-d) δ = 159.1, 137.0,

134.8, 130.3, 129.3, 127.6, 127.2, 126.6, 126.1, 114.1, 55.3, 21.2.

.55−7.41 (m, 2H), 7.02 (s, 1H), 6.98−6.91 (m, 2H), 6.91−6.87 (m,

H), 6.67 (d, J = 2.1 Hz, 2H), 6.39 (t, J = 2.2 Hz, 1H), 3.84 (s, 9H).

C NMR{ H} (50 MHz, chloroform-d) δ = 161.0, 159.4, 139.7,

(E)-1-(4-Methoxystyryl)-3-methylbenzene (4c).

The title com-

pound was synthesized according to the general procedure described

in section 2A. The product was puriﬁed using silica gel (230−400

mesh) column chromatography using a mixture of petroleum ether/

EtOAc as an eluent. White solid. Yield: 71%, 159 mg. H NMR (200

MHz, chloroform-d) δ = 7.45 (d, J = 8.3 Hz, 2H), 7.31−7.28 (m,

129.9, 128.7, 127.8, 126.6, 114.1, 104.3, 99.6, 55.3.

(E)-5-(4-Hydroxystyryl)benzene-1,3-diol (6). Colorless liquid.

Yield: 74%, 169 mg. H NMR (200 MHz, DMSO-d ) δ = 8.59 (s,

1H), 8.25 (s, 2H), 6.32 (d, J = 8.6 Hz, 2H), 5.89−5.61 (m, 4H), 5.33

13 1

(s, 2H), 5.17−4.95 (m, 1H). C NMR{ H} (50 MHz, DMSO-d ) δ

H), 7.23 (t, J = 6.7 Hz, 1H), 7.08−7.03 (m, 2H), 6.97 (s, 1H), 6.90

= 158.6, 157.3, 139.5, 128.3, 128.0, 125.8, 115.7, 104.5, 102.0.

(

d, J = 9.4 Hz, 2H), 3.83 (s, 3H), 2.37 (s, 3H). C NMR{ H} (50

MHz, chloroform-d) δ = 159.2, 138.1, 137.5, 130.2, 128.5, 128.0,

28.0, 127.6, 126.9, 126.7, 123.4, 114.1, 55.3, 21.4.

ASSOCIATED CONTENT

■

(

E)-2-(4-Methoxystyryl)naphthalene (4d). The title compound

sı Supporting Information

was synthesized according to the general procedure described in

section 2A. The product was puriﬁed using silica gel (230−400 mesh)

column chromatography using a mixture of petroleum ether/EtOAc

The Supporting Information is available free of charge at

as an eluent. White solid. Yield: 73%, 190 mg. H NMR (200 MHz,

Experimental and spectroscopic data, copies of H and

chloroform-d) δ = 7.84−7.72 (m, 5H), 7.54−7.43 (m, 4H), 7.18 (s,

C NMR spectra, and HRMS (PDF)

2H), 6.94 (d, J = 9.9 Hz, 2H), 3.86 (s, 3H). C NMR{ H} (50 MHz,

chloroform-d) δ = 152.4, 133.8, 132.8, 130.2, 128.6, 127.9, 127.7,

26.7, 126.3, 126.1, 125.7, 123.5, 114.2, 55.3.

E)-1,2,3-Trimethoxy-5-(4-methoxystyryl)benzene (4e).

FAIR data, including the primary NMR FID ﬁles, for

compounds 3a−3d, 3f, 3k −3n, 3p−3r, 3w, 3y, 3za−

(

The

ze, 4a−4d, 4i, and 7−8 (ZIP)

title compound was synthesized according to the general procedure

described in section 2A. The product was puriﬁed using silica gel

(

230−400 mesh) column chromatography using a mixture of

AUTHOR INFORMATION

petroleum ether/EtOAc as an eluent. White solid. Yield: 83%, 249

mg. H NMR (200 MHz, chloroform-d) δ = 7.46 (d, J = 8.8 Hz, 2H),

■

Corresponding Author

.00−6.91 (m, 3H), 6.73 (s, 2H), 3.92 (s, 6H), 3.88 (s, 3H), 3.84 (s,

_H₎_.₁3C NMR{1H} (50 MHz, chloroform-d) δ = 159.3, 153.4, 137.7,

Ekambaram Balaraman − Department of Chemistry, Indian

Institute of Science Education and Research (IISER)

Tirupati, Tirupati 517507, India; orcid.org/0000-0001-

9248-2809 ; Email: eb.raman@iisertirupati.ac.in

33.4, 130.0, 127.7, 127.6, 126.5, 114.1, 103.4, 60.9, 56.1, 55.3.

(E)-1,2-Dip-tolylethene (4f).

The title compound was synthe-

sized according to the general procedure described in section 2A. The

560

J. Org. Chem. 2021, 86, 7552−7562

The Journal of Organic Chemistry

Kirchner, K. Isoelectronic Manganese and Iron Hydrogenation/

Article

Authors

Electrophiles. Chem. Rev. 2010, 110, 1611−1641.

Siba P. Midya − Department of Chemistry, Indian Institute of

Science Education and Research (IISER)Tirupati,

Tirupati 517507, India

Murugan Subaramanian − Department of Chemistry, Indian

Institute of Science Education and Research (IISER)

Tirupati, Tirupati 517507, India

Reshma Babu − Department of Chemistry, Indian Institute of

Science Education and Research (IISER)Tirupati,

Tirupati 517507, India

(9) For selected reviews of AD strategy, see: (a) Gorgas, N.;

Dehydrogenation Catalysts: Similarities and Divergences. Acc. Chem.

Res. 2018, 51, 1558−1569. (b) Sordakis, K.; Tang, C.; Vogt, L. K.;

Junge, H.; Dyson, P. J.; Beller, M.; Laurenczy, G. Homogeneous

Catalysis for Sustainable Hydrogen Storage in Formic Acid and

Alcohols. Chem. Rev. 2018 , 118 , 372 −382. (c) Crabtree, R. H.

Homogeneous Transition Metal Catalysis of Acceptorless Dehydro-

genative Alcohol Oxidation: Applications in Hydrogen Storage and to

Heterocycle Synthesis. Chem. Rev. 2017 , 117 , 9228 −9246. (d) Guna-

nathan, C.; Milstein, D. Applications of Acceptorless Dehydrogen-

Vinita Yadav − Organic Chemistry Division, CSIR-National

Chemical Laboratory (CSIR-NCL), Pune 411008, India

Complete contact information is available at:

https://pubs.acs.org/10.1021/acs.joc.1c00592

013, 341 , 1229712. (e) Werkmeister, S.; Neumann, J.; Junge, K.;

Beller, M. Pincer-Type Complexes for Catalytic (De)Hydrogenation

and Transfer (De)Hydrogenation Reactions: Recent Progress. Chem. -

Eur. J. 2015, 21, 12226−12250. (f) Balaraman, E.; Nandakumar, A.;

Jaiswal, G.; Sahoo, M. K. Iron-Catalyzed Dehydrogenation Reactions

and their Applications in Sustainable Energy and Catalysis. Catal. Sci.

Technol. 2017 , 7 , 3177 −3195. (g) Maji, B.; Barman, M. K. Recent

Developments of Manganese Complexes for Catalytic Hydrogenation

and Dehydrogenation Reactions. Synthesis 2017 , 49 , 3377 −3393.

Notes

The authors declare no competing ﬁnancial interest.

ACKNOWLEDGMENTS

This work is supported by the SERB, India (No. CRG/2018/

02480), and IISER-Tirupati. E.B. acknowledges the Swarna-

■

(h) Kallmeier, F.; Kempe, R. Manganese Complexes for (De)-

Jayanti Fellowship grant (DST/SJF/CSA-04/2019-2020 and

SERB/F/5892/2020-2021). R.B. thanks SERB-PMRF, India,

for a fellowship. M.S. and V.Y. acknowledge the UGC, India,

for their fellowships.

Hydrogenation Catalysis: A Comparison to Cobalt and Iron Catalysts.

Angew. Chem., Int. Ed. 2018, 57, 46−60.

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Catalytic Olefination of Alcohols with Sulfones. Angew. Chem., Int. Ed.

014 , 53 , 11092 −11095. (b) Khaskin, E.; Milstein, D. Catalytic,

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