A Facile Transition Metal-Free Ionic Liquid [BMIM]OH Mediated Regio- and Stereoselective Hydrocarboxylation of Alkynylnitriles

Article abstract of DOI:10.1002/ejoc.202001369

We report an efficient and straight forward access to nitrile substituted enol esters via ionic liquid [BMIM]OH mediated hydrocarboxylation of alkynylnitriles under mild conditions. This atom economical transition metal-free protocol gives an easy access to a variety of such enol esters with excellent regio and Z-stereoselectivity. Reusability of [BMIM]OH without losing of significant amount of yield is another noticeable feature of this article.

Full text of DOI:10.1002/ejoc.202001369

Full Papers
doi.org/10.1002/ejoc.202001369
1
2
3
4
5
6
7
8
9
A Facile Transition Metal-Free Ionic Liquid [BMIM]OH
Mediated Regio- and Stereoselective Hydrocarboxylation of
Alkynylnitriles
Chandresh Kumari[a] and Avijit Goswami*[a]
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
We report an efficient and straight forward access to nitrile
substituted enol esters via ionic liquid [BMIM]OH mediated
hydrocarboxylation of alkynylnitriles under mild conditions. This
atom economical transition metal-free protocol gives an easy
access to a variety of such enol esters with excellent regio and
Z-stereoselectivity. Reusability of [BMIM]OH without losing of
significant amount of yield is another noticeable feature of this
article.
Introduction
lengthy troublesome procedures, poisonous reagents and costly
ligands, while reports on metal free hydrocarboxylation reac-
tions are rather limited.[16]
Enol esters are the most versatile moieties to construct different
organic scaffolds thus play a significant role in a variety of
synthetic transformations.[1] Owing to their immense impor-
tance as substrates and intermediates in organic synthesis,
polymer and pharmaceutical chemistry, various attempts have
been made to synthesize substituted enol esters. So far, a large
number of methodologies has been developed for the synthesis
of enol esters.[2] Among different approaches for the synthesis
of enol esters, the direct addition of carboxylic acids to alkynes
is the most widely used atom economical approach. However, it
is very challenging to control the regio- and stereoselecivity
during the addition process especially in the case of unsym-
metrically substituted internal alkynes.[3] Therefore, the main
focus of the ongoing research has been devoted towards the
efficient synthesis of widely substituted stereo-defined enol
esters, by the use of specific reagents and catalysts. A large
number of transition metal complexes of ruthenium,[3b–d,4]
palladium,[5] rhodium,[6] iridium,[7] cobalt,[8] rhenium,[9] silver,[10]
iron,[11] copper,[12] and mercury[13] are utilized for the hydro-
carboxylation of the alkynes to synthesize substituted enol
esters. However, it has been observed that the regio- and
stereoselectivity of the metal catalyzed organic transformations
strongly depends on the ligand environment around the metal
centre. Therefore, lot of efforts have been employed in
literature to tailor the synthesis of metal complexes and ligands
to achieve the required regio- and stereoselectivity.[3e,5d,14] In
addition, gold catalysts have also been extensively used for the
intermolecular addition of carboxylic acids to alkynes.[14a,e,15]
Most of these aforementioned approaches are assisted by either
toxic or expensive metal salts, drastic reaction conditions,
During the course of our research on chemoselective 1-
butyl-3-methylimidazolium hydroxide [BMIM]OH[17] catalyzed 2-
(phenylethynyl)-4H-benzo[d][1,3]oxazin-4-one synthesis from
phenylacetylenenitrile, we obtained nitrile substituted enol
1
ester as a sole isolated product in good yield. H-NMR and 2D
NOE analysis showed the formation of Z enol ester with
complete regioselectivity. So far, only two reports can be found
in the literature on nitrile substituted enol ester synthesis
(Scheme 1). The first one reported by Mansour in 1988,
documented only three examples of nitrile substituted enol
esters as mixtures of E and Z isomers synthesized from
benzoylacetonitriles and benzoyl bromide by using diisopropy-
lethylamine (DIPEA), MgCl2 in DCM (Scheme 1a).[18] In 2017,
Cadierno et al. reported the [AuCl(PPh3)]/AgOAc (5 mol%)
catalyzed addition of carboxylic acids to internal alkynes.[14e]
[a] C. Kumari, Dr. A. Goswami
Department of Chemistry, Indian Institute of Technology Ropar,
Nangal Road, Rupnagar, Punjab 140001, India
E-mail: agoswami@iitrpr.ac.in
https://sites.google.com/a/iitrpr.ac.in/iitropar-chemistry/faculty/dr-avijit-
goswami
Supporting information for this article is available on the WWW under
https://doi.org/10.1002/ejoc.202001369
Scheme 1. Synthesis of nitrile substituted Z-enol esters.
Eur. J. Org. Chem. 2020, 1–8
1
© 2020 Wiley-VCH GmbH
��
These are not the final page numbers!

Full Papers
doi.org/10.1002/ejoc.202001369
This approach demonstrated only one example of nitrile
substituted enol ester with Z stereoselectivity but with lower
yield (Scheme 1b).
of optimization, however, couldn’t give the expected product in
the absence of base (Table 1, entry 13). On the contrary, when
K2CO3 was used as a base, Z enol ester was obtained as a sole
isolated product in 60% yield (Table 1, entry 14). Moreover,
increased temperature resulted in decreased yield along with
the formation of undesired side products (Table 1, entry 15).
With this protocol in hand, the scope of the formation of
nitrile substituted enol esters in [BMIM]OH was examined in
presence of widely substituted aliphatic and aromatic carboxylic
acids with various alkynylnitriles. As shown in Scheme 2, a wide
range of enol esters were synthesized with complete regio- and
Z stereoselectivity in good to excellent yields, indicating the
remarkable functional group compatibility of this protocol.
Benzoic acids with functional groups at different positions of
the aromatic ring, including electron rich and electron poor
groups (methyl, methoxy, amine, iodo, chloro, flouro and nitro
groups) were well tolerated. Observation showed that benzoic
acids with electron donating groups were more effective than
with electron withdrawing groups most likely due to their
enhanced nucleophilicity. As expected, most acidic hexaflour-
obenzoic acid (3as) and trichloroacetic acid (3at) afforded no
adducts. In addition, aliphatic carboxylic acids (3ao and 3ap)
showed good reactivity. Heteroaryl carboxylic acids were also
able to give good yields for the desired esters. Although
pyridine-2-carboxylic acid (3au) could not give the desired
product, 2-furoicacid (3ar), indole 2-carboxylic acid (3aq) and
3-bromo-2-thiophenecarboxylic acid (3an) gave the corre-
sponding enol esters in good yields. Compounds 3aa, 3ab,
3ah, 3al, 3ch, 3am, 3aq, 3ai and 3aj were isolated as pure
single crystals and the structures were confirmed by single-
crystal X-ray analysis (Figure 1).[19]
1
2
3
4
5
6
7
8
9
As nitriles are versatile precursors to build other useful
functional groups, synthesizing stereo-defined nitrile-substi-
tuted enol esters in a green, atom economical, straight forward
way would be quite appealing. To the best of our knowledge,
report of a highly efficient, transition metal-free, ionic liquid
[BMIM]OH mediated exclusive regio- and stereoselective nitrile
substituted enol ester formation has not been disclosed to date.
In this article, we have reported the synthesis of nitrile
substituted enolesters in complete Z-stereoselection fashion
with the reusability of the ionic liquid up to ten runs without
loss of activity.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
Results and Discussion
We commenced our studies with phenylacetytelenentrile (1a)
and benzoic acid (2a) as model substrates for the enol ester
synthesis via metal-free [BMIM]OH mediated regio- and stereo-
selective addition reaction and the results are summarized in
Table 1. Initially, [BMIM]OH was tested in a stochiometric
amount in water as well as in acetonitrile at room and elevated
temperatures, however none of these experiments could give
us satisfactory results (Table 1, entries 1–4). On the other hand,
when [BMIM]OH used as a solvent we obtained the expected
product in 70% yield in 12 hours (Table 1, entry 5). In parallel, a
set of bases was surveyed and it was found K2CO3, Cs2CO3, NEt3
afforded the desired product in acetonitrile but as inseparable
isomeric mixture (Table 1, entries 7–9). At the same time,
reaction with K2CO3 as a base and TBAF as a phase transfer
reagent in water resulted in the formation of enol ester in 70%
yield with a mixture of E and Z stereoisomers (Table 1, entry 12).
Another ionic liquid [BMIM]Br was also exploited in the course
Table 2 summarized the results of addition of benzoic acid
to the non nitrile substituted terminal and internal alkynes. It is
found that addition of benzoic acid to the terminal alkynes,
symmetrical and unsymmetrical internal alkynes (Table 2, en-
Table 1. Optimization conditions for the addition reaction of benzoic acid to phenylacetylenenitrile.[a]
Entry
Base [equiv.]
Solvent [ml]
Temp [ C]
Time [h]
Yield[b] [%]
°
(3aa:3’aa)
traces
1
2
3
4
5
6
7
8
[BMIM]OH (1)
[BMIM]OH (1)
[BMIM]OH (1)
[BMIM]OH (1)
–
K2CO3 (0.5)
K2CO3 (0.5)
NEt3 (1)
Cs2CO3 (0.5)
TBAF (1)
TBAF (1)
K2CO3/TBAF (0.5/1)
–
K2CO3 (0.5)
K2CO3 (0.5)
H2O (1)
H2O (1)
rt
55
rt
55
rt
rt
rt
rt
rt
rt
rt
rt
rt
rt
75
12
12
12
12
12
12
12
12
12
36
36
36
12
12
12
traces
MeCN (1)
MeCN (1)
[BMIM]OH (2)
DMF (1)
MeCN (1)
MeCN (1)
MeCN (1)
H2O (1)
MeCN (1)
H2O (1)
[BMIM]Br (2)
[BMIM]Br (2)
[BMIM]Br (2)
50 (1.2:1)[c]
37 (1.2:1)[c]
70 (1:0)
traces
39 (1.2:1)[c]
46 (1.2:1)[c]
50 (1.7:1)[c]
30 (1.1:1)[c]
39 (1.1:1)[c]
70 (1.2:1)[c]
–
9
10
11
12
13
14
15
60 (1:0)
30 (1:0)
[a] Optimized reaction conditions: 1a (63.5 mg, 0.5 mmol) and 2a (61 mg, 0.5 mmol), [BMIM]OH (1 ml), rt, 12 h. [b] isolated yield. [c] ratio determined by 1H-
NMR.
Eur. J. Org. Chem. 2020, 1–8
www.eurjoc.org
2
© 2020 Wiley-VCH GmbH
��
These are not the final page numbers!

Full Papers
doi.org/10.1002/ejoc.202001369
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
Scheme 2. Addition of carboxylic acids to alkynylnitriles: 1 (0.5 mmol) and 2 (0.5 mmol), [BMIM]OH (1 ml), rt,12 h.
Table 2. [BMIM]OH mediated addition of benzoic acid to various alkynes.[a]
Entry
R1
R2
Yield[b] [%]
4:4’
1
2
3
4
5
6
Ph
Ph
Ph
COOEt
Ph
Ph
H
Ph
COOEt
COOEt
SeCN
SCN
traces
traces
traces
50
no reaction
no reaction
–
–
–
1:0
–
–
[a] Optimized reaction conditions: 1a (0.5 mmol) and 2a (0.5 mmol),
[BMIM]OH (1 ml), rt, 12 h, [b] isolated yield.
tries 1, 2, 5 and 6) did not afford the desired enolesters, even
internal alkyne with electron withdrawing group like ester also
failed (Table 2, entry 3). Highly activated internal alkyne with
diester groups afforded 50% yield with Z stereoselectivity
(Table 2, entry 4). However, internal alkyne with nitrile group
Figure 1. X- ray crystal structures of enol esters.
Eur. J. Org. Chem. 2020, 1–8
www.eurjoc.org
3
© 2020 Wiley-VCH GmbH
��
These are not the final page numbers!

Full Papers
doi.org/10.1002/ejoc.202001369
gave the corresponding enol ester in good yield with excellent
The reusability of the ionic liquid [BMIM]OH was also
checked for the synthesis of 3aa and 3ah from the reaction of
corresponding alkynylnitriles (1) and aromatic carboxylic acids
(2). After each run, the reaction mixture was extracted with
ether. The ionic liquid left was reused for the next run after
drying under vacuum. The ionic liquid [BMIM]OH could be
effectively used for 10 cycles without noticeable loss in the
quantity of the ionic liquid and the isolated yields of 3aa and
3ah (Figure 2).
Interestingly, 1.2 g of 3ah with 82% yield was obtained
from 1a and 2h when the addition reaction was carried out at
5 mmol scale under optimized reaction conditions (Scheme 4),
which shows the general applicability and large-scale produc-
tivity of this protocol.
Encouraged by these excellent results of this protocol, we
then moved towards some important transformations of enol
esters (Scheme 5). To our delight, treating 3ab with stochio-
metric amount of Ag2O and DMAP in ACN led to biologically
important,[21] nitrile substituted isocoumarin 5 in 77% yield. In
addition, heating 3aa with DMAP gave 2-cyano-1,3-diphenyl-
1,3-propanedione 6 in 84% yield.
1
2
3
4
5
6
7
8
9
stereoselectivity as shown earlier. This shows that the nitrile
group of alkynylnitrile in presence of [BMIM]OH plays a
significant role in directing the reactants to result in a complete
regio- and Z stereoselective enol esters.
On the basis of experimental results and literature survey,[20]
the plausible mechanism for the [BMIM]OH mediated hydro-
carboxylation of alkynylnitriles is proposed in Scheme 3. Initially,
the cationic imidazolium ring would coordinate to the nitrile
group of the alkynylnitrile in η5-fashion to form complex A,
while the hydroxide ion would deprotonate the carboxylic acid
to generate carboxylate ion. Subsequent nucleophilic attack of
carboxylate ion on the more electrophilic carbon of the
activated alkyne in complex A leads to complex B, followed by
complex C in which the negative charge is stabilized by the
cationic imidazolium ring and subsequently, it is replaced by
the proton of the eliminated water. Then, as a result, the
regeneration of the [BMIM]OH takes place and catalytic cycle
remains continue. In this context, it is important to mention
that stereochemistry of the complex C helps us to access the Z-
enol ester product exclusively.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
Conclusion
In summary, we have reported the first example of transition
metal-free ionic liquid mediated hydrocarboxylation of alkynyl-
nitriles, leading to a library of nitrile substituted enol esters. The
operational simplicity, high efficiency, use of easily available
inexpensive reagents, mild reaction conditions, high atom
economic, general applicability, recyclability of the ionic liquid
and complete regio- and stereoselectivity are the salient
features of this approach.
Scheme 3. Plausible Mechanism.
Scheme 4. [BMIM]OH mediated hydrocarboxylation reaction for the gram
scale synthesis of 3ah: 1a (0.635 g, 5 mmol), 2h (0.76 g, 5 mmol), [BMIM]OH
(3 ml), rt, 12 h; [b] isolated yield.
Figure 2. Reusability studies of ionic liquid [BMIM]OH for the synthesis of
3aa and 3ah.
Scheme 5. Synthetic applications of enolesters.
Eur. J. Org. Chem. 2020, 1–8
www.eurjoc.org
4
© 2020 Wiley-VCH GmbH
��
These are not the final page numbers!

Full Papers
doi.org/10.1002/ejoc.202001369
160.6 (d, J=4 Hz), 136.3(d, J =9 Hz), 132.9, 132.0, 131.5, 129.3,
Experimental Section
1
2
3
4
5
6
7
8
9
125.8, 124.6 (d, J=3.7 Hz), 117.5 (d, J=21.3 Hz), 116.5(d, J=
9.4 Hz),114.6, 87.6; HRMS: m/z calculated for C16H11 F NO2 [M+H]+
:
General Information: Chemicals and reagents were purchased from
commercial suppliers and used without further purification. Thin
layer chromatography (TLC) was performed using pre-coated plates
purchased from E. Merck (silica gel 60 PF254, 0.25 mm). Column
chromatography was performed using E. Merck silica gel 60 (100–
200 mesh. NMR spectra were recorded in CDCl3, on JEOL JNM-ECS
spectrometer at operating frequencies of 400 MHz (1H) or 100 MHz
(13C) as indicated in the individual spectrum. Chemical shifts (δ) are
given in ppm relative to residual solvent (chloroform, δ=7.26 for
1H and 77.16 for proton decoupled 13C NMR) and coupling
constants (J) in Hz. Multiplicity is tabulated as s for singlet, d for
doublet, dd for doublet of doublet, t for triplet, q for quartet and m
for multiplet. High-resolution mass spectra (HRMS) were recorded
using electron spray ionization (ESI) methods on waters mass
spectrometer. Melting points were determined using BIBBY-SMP30
melting point meter. Single crystal X-ray structural data was
collected on a CMOS based Bruker D8 Venture PHOTON 100
diffractometer equipped with a INCOATEC micro-focus source with
graphite monochromated Mo Kα radiation (λ=0.71073 A) operat-
ing at 50 kV and 30 mA. The 1-alkynyl nitriles (1a–d),[22] were
prepared according to the reported literature procedure.
268.0774; found: 268.0745.
(Z)-2-Cyano-1-phenylvinyl 2-nitrobenzoate (3ae): Yield: 85.26 mg
1
°
(58%); m.p. 107–111 C; H NMR (400 MHz, CDCl3): δ 8.13–8.07 (m,
2H), 7.82 (td, J=7.6, 1.3 Hz, 1H), 7.75 (td, J=7.7, 1.8 Hz, 1H), 7.71–
7.67 (m, 2H), 7.56–7.46 (m, 3H), 5.84 (s, 1H); 13C NMR (100 MHz,
CDCl3): δ 164.3, 162.1, 147.6, 134.0, 132.8, 132.5, 130.9, 130.6, 129.4,
126.4, 126.3, 124.5, 114.7, 87.8; HRMS: m/z calculated for C16H11N2O4
[M+H]+ : 295.0719; found: 295.0710.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
(Z)-2-Cyano-1-phenylvinyl 2,6-difluorobenzoate (3af): Yield:
1
97 mg (68%); H NMR (400 MHz, CDCl3): δ 7.64–7.60 (m, 2H), 7.58–
7.54 (m, 1H), 7.53–7.48 (m, 1H), 7.47–7.43 (m, 2H), 7.06 (t, J=8.6 Hz,
2H), 5.81 (s, 1H); 13C NMR (100 MHz, CDCl3): δ 163.7, 161.5 (dd, J=
260, 5.1 Hz), 157.7, 134.8 (t, J=10.8 Hz), 132.1, 131.1, 129.3, 125.9,
114.3, 112.6 (dd, J=21.8, 3.7 Hz), 108.6 (t, J=16.2 Hz), 87.9; HRMS:
m/z calculated for C16H10 F2 NO2 [M+H]+: 286.0680; found:
286.0663.
(Z)-2-Cyano-1-phenylvinyl 4-chloro-2-iodobenzoate (3ag): Yield:
1
°
143 mg (70%); m.p. 115–118 C; H NMR (400 MHz, CDCl3): δ 8.17 (d,
J=8.2 Hz, 1H), 8.12 (d, J=2.2 Hz, 1H), 7.58–7.55 (m, 2H), 7.53–7.49
(m, 2H), 7.46–7.42 (m, 2H), 5.81 (s, 1H); 13C NMR (100 MHz, CDCl3): δ
164.2, 161.7, 141.8, 140.0, 132.9, 132.2, 131.2, 130.2, 129.3, 128.8,
125.8, 114.6, 95.9, 87.7; HRMS: m/z calculated for C16H10 ClINO2 [M+
H]+ :409.9445; found: 409.9454.
General procedure for the synthesis of compound 3: In a round
bottom flask, a mixture of 1-alkynyl nitrile 1 (0.5 mmol), carboxylic
acid 2 (0.5 mmol) and [BMIM]OH (1 ml) was stirred for 12 hours at
room temperature. After completion of reaction checked by TLC,
the product was extracted with ether (3*20 mL and evaporated
under reduced pressure. The crude was further purified through
column chromatography over silica gel (100–200 mesh) with
EtOAc/hexane as elute. After isolation of the product, the remaining
ionic liquid was washed with ether (3x10 mL) to remove organic
impurity and evaporated under reduced pressure to afford [BMIM]
OH, which was reused in subsequent runs without further
purification.
(Z)-2-Cyano-1-phenylvinyl 4-methoxybenzoate (3ah): Yield:
1
°
122.8 mg (88%); m.p. 95–100 C; H NMR (400 MHz, CDCl3): δ 8.17
(d, J=9.1 Hz, 2H), 7.56–7.54 (m, 2H), 7.49–7.45 (m, 1H), 7.43–7.38
(m, 2H), 7.01 (d, J=8.9 Hz, 2H), 5.79 (s, 1H), 3.90 (s, 3H); 13C NMR
(100 MHz, CDCl3): δ 164.7, 164.6, 162.9, 132.9, 131.9, 129.2, 125.7,
120.0, 114.8, 114.3, 87.3, 55.7; HRMS: m/z calculated for C17H14 NO3
[M+H]+ : 280.0974; found: 280.0946.
(Z)-2-Cyano-1-phenylvinyl 2-iodo-5-methylbenzoate (3ai): Yield:
1
°
145.9 mg (75%); m.p. 102–104 C; H NMR (400 MHz, CDCl3): δ 8.03
Characterization of compounds:
(d, J=1.95 Hz, 1H), 7.95(d, J=8.1 Hz, 1H), 7.60–7.57 (m, 2H), 7.52–
7.48 (m, 1H), 7.46–7.42 (m, 2H), 7.10(dd, J=8.1, 1.9 Hz, 1H), 5.81 (s,
1H), 2.41(s, 1H); 13C NMR (100 MHz, CDCl3): δ 164.4, 162.5, 142.0,
138.8, 135.3, 133.0, 132.1, 131.7, 131.4, 129.3, 125.9, 114.7, 91.4,
(Z)-2-Cyano-1-phenylvinylbenzoate (3aa): Yield: 87 mg (70%);
1
°
m.p. 95–97 C; H NMR (400 MHz, CDCl3): δ 8.24 (d J=7.9 Hz, 2H),
7.71–7.67 (m, 1H), 7.58–7.53 (m, 4H), 7.50–7.46 (m, 1H), 7.43–7.39
(m, 2H), 5.83 (s, 1H); 13C NMR (100 MHz, CDCl3): δ 164.3, 163.1,
134.5, 131.9, 131.5, 130.5, 129.1, 128.9, 127.7, 125.6, 114.6, 87.4;
HRMS: m/z calculated for C16H12 NO2[M+H]+: 250.0868; found:
250.0874.
87.6, 21.0; HRMS: m/z calculated for C17H13 I NO2 [M+H]+
:
389.9991; found: 389.9971.
(Z)-2-Cyano-1-phenylvinyl 2-amino-4,5-dimethoxybenzoate (3aj):
1
°
Yield: 121.5 mg (75%); m.p. 170–175 C; H NMR (400 MHz, CDCl3): δ
(Z)-2-Cyano-1-phenylvinyl 2-iodobenzoate (3ab): Yield: 142.5 mg
7.57–7.54 (m, 2H), 7.49–7.46 (m, 2H), 7.43–7.39 (m, 2H), 6.16 (s, 1H),
5.78 (s, 1H), 5.63 (s, broad, 2H), 3.89 (s, 3H), 3.88 (s, 3H); 13C NMR
(100 MHz, CDCl3): δ 164.7, 164.1, 156.6, 149.3, 141.1, 132.2, 131.8,
129.2, 125.7, 115.0, 112.1, 99.1, 98.9, 87.2, 56.6, 56.0; HRMS: m/z
calculated for C18H17 N2O4 [M+H]+: 325.1188; found: 325.1162.
1
°
(76%); m.p. 98–101 C; H NMR (400 MHz, CDCl3): δ 8.21 (dd, J=7.8,
1.5 Hz, 1H), 8.07 (d, J=8.0 Hz, 1H), 7.58–7.56 (m, 2H), 7.52–7.46 (m,
2H), 7.43–7.39 (m, 2H), 7.27–7.23 (m, 1H), 5.81 (s, 1H); 13C NMR
(100 MHz, CDCl3): δ 164.2, 162.4, 142.07, 134.1, 132.1, 132.0, 131.9,
131.2, 129.2, 128.4, 125.7, 114.6, 95.2, 87.5; HRMS: m/z calculated for
C16H11 I NO2 [M+H]+ : 375.9834; found: 375.9827.
(Z)-2-Cyano-1-phenylvinyl 2-methyl-3-nitrobenzoate (3ak): Yield:
1
°
104.72 mg (68%); m.p. 100–104 C; H NMR (400 MHz, CDCl3): δ 8.39
(Z)-2-Cyano-1-phenylvinyl 2-chlorobenzoate (3ac): Yield: 106 mg
(d, J=7.8 Hz, 1H), 7.97(d, J=8.3 Hz, 1H), 7.56–7.50 (m, 4H), 7.49–
7.44 (m, 2H), 5.84 (s, 1H), 2.68(s, 3H); 13C NMR (100 MHz, CDCl3): δ
164.2, 162.3, 152.4, 134.9, 134.5, 132.3, 131.3, 130.4, 129.4, 128.2,
127.1, 125.7, 114.7, 87.9, 16.3; HRMS: m/z calculated for C17H13 N2O4
[MÀ H]+ : 307.0719; found: 307.0700.
1
°
(75%); m.p. 84–87 C; H NMR (400 MHz, CDCl3): δ 8.19 (d, J=7.7 Hz,
1H), 7.61–7.58 (m, 2H), 7.56–7.54 (m, 2H), 7.51–7.48 (m, 1H), 7.46–
7.41 (m, 3H), 5.81 (s, 1H); 13C NMR (100 MHz, CDCl3): δ 164.3, 161.6,
135.0, 134.2, 132.5, 132.1, 131.6, 131.4, 129.2, 127.4, 127.1, 125.8,
114.6, 87.6; HRMS: m/z calculated for C16H11 Cl NO2 [M+H]+:
284.0478; found: 284.0451.
(Z)-2-Cyano-1-phenylvinyl 3-methyl-2-nitrobenzoate (3al): Yield:
1
°
100 mg (65%); m.p. 128–130 C; H NMR (400 MHz, CDCl3): δ 8.13 (d,
(Z)-2-Cyano-1-phenylvinyl 2-fluorobenzoate (3ad): Yield: 96 mg
J=7.6 Hz, 1H), 7.64–7.58 (m, 2H), 7.56–7.48 (m, 3H), 7.46–7.42 (m,
2H), 5.79 (s, 1H), 2.40 (s, 3H); 13C NMR (100 MHz, CDCl3): δ 163.9,
160.2, 150.8, 137.1, 132.3, 131.4, 130.9, 130.5, 129.5, 129.4, 125.8,
121.3, 114.3, 87.9, 17.4; HRMS: m/z calculated for C17H13 N2O4 [M+
H]+ : 309.0875; found: 309.0853.
1
°
(72%); m.p. 99–104 C; H NMR (400 MHz, CDCl3): δ 8.14 (td, J=7.3,
1.8 Hz, 1H), 7.69–7.63 (m, 1H), 7.60–7.58 (m, 2H), 7.52–7.47 (m, 1H),
7.45–7.41 (m, 2H), 7.31 (td, J=7.5, 1.2 Hz, 1H), 7.27–7.22 (m, 1H),
5.81 (s, 1H); 13C NMR (100 MHz, CDCl3): δ 164.2, 163 (d, J=262 Hz),
Eur. J. Org. Chem. 2020, 1–8
www.eurjoc.org
5
© 2020 Wiley-VCH GmbH
��
These are not the final page numbers!

Full Papers
doi.org/10.1002/ejoc.202001369
(Z)-2-Cyano-1-phenylvinyl 4-nitrobenzoate (3am): Yield: 88.2 mg
1H), 8.08 (dd, J=8.2, 1.0 Hz, 1H), 7.60–7.56 (m, 2H), 7.51 (t, J=
7.6 Hz, 1H), 7.26 (t, J=7.6 Hz, 1H), 7.11 (t, J=8.6 Hz, 2H), 5.76 (s,
1H); 13C NMR (100 MHz, CDCl3): δ 164.8 (d, J=254.8 Hz), 163.2,
162.4, 142.1, 134.3, 132.2, 131.8, 128.5, 128.2 (d, J=9 Hz), 127.6 (d,
J=2.9 Hz)„ 116.5 (d, J=21.6 Hz), 114.4, 95.3, 87.5; HRMS: m/z
calculated for C16H10 FI NO2 [M+H]+ : 393.9740; found: 393.9729
1
2
3
4
5
(60%); m.p. 180–185 C; 1H NMR (400 MHz, CDCl3): δ 8.40 (s, 4H),
°
7.56–7.50 (m, 3H), 7.47–7.42 (m, 2H), 5.86 (s, 1H); 13C NMR (100 MHz,
CDCl3): δ 164.0, 161.5, 151.5, 133.2, 132.4, 131.8, 131.0, 129.4, 125.7,
124.2, 114.4, 88.0; HRMS: m/z calculated for C16H11N2O4 [M+H]+
:
295.0719; found: 295.0691.
6
7
8
9
(Z)-2-Cyano-1-phenylvinyl
3-bromothiophene-2-carboxylate
(Z)-2-Cyano-1-(p–tolyl)vinyl 4-methoxybenzoate (3ch): Yield:
1
1
°
(3an): Yield: 116.6 mg (70%); H NMR (400 MHz, CDCl3): δ 7.66 (d,
J=5.2 Hz, 1H), 7.58–7.55 (m, 2H), 7.52–7.47 (m, 1H), 7.45–7.41 (m,
2H), 7.21 (d, J=5.4 Hz, 1H), 5.80 (s, 1H); 13C NMR (100 MHz, CDCl3): δ
163.6, 156.9, 133.8, 132.1, 131.5, 129.3, 125.8, 124.8, 124.1, 120.6,
132.3 mg (90%); m.p. 145–155 C; H NMR (400 MHz, CDCl3): δ 8.17
(d, J=9.1 Hz, 2H), 7.43(d, J=8.4 Hz, 2H), 7.20(d, J=8.2 Hz, 2H), 7.00
(d, J=9.1 Hz, 2H), 5.73 (s, 1H), 3.90 (s, 3H), 2.37(s, 3H); 13C NMR
(100 MHz, CDCl3): δ 164.8, 164.7, 162.9, 142.7, 132.9, 129.9, 129.2,
125.7, 120.2, 115.1, 114.3, 86.3, 55.7, 21.6; HRMS: m/z calculated for
C18H16 NO3 [M+H]+ : 294.1130; found: 294.1104
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
114.5, 88.0; HRMS: m/z calculated for C14H9BrNO2S [M+H]+
:
333.9537; found: 333.9516.
1
(Z)-2-Cyano-1-phenylvinyl acetate (3ao): Yield: 64.5 mg (69%); H
NMR (400 MHz, CDCl3): δ 7.52–7.46 (m, 3H), 7.45–7.39 (m, 2H), 5.71
(s, 1H), 2.40 (s, 3H); 13C NMR (100 MHz, CDCl3): δ 167.2, 164.2, 132.0,
131.5, 129.2, 125.6, 114.7, 87.3, 20.7; HRMS: m/z calculated for C16H10
F2 NO2 [MÀ H]+ : 186.0555; found 186.0537.
(Z)-2-Cyano-1-(4-fluorophenyl)vinyl 4-methoxybenzoate (3bh):
1
°
Yield: 126.2 mg (85%); m.p. 90–95 C; H NMR (400 MHz, CDCl3): δ
8.16 (d, J=8.6 Hz, 2H), 7.57–7.53 (m, 2H), 7.09 (t, J=8.6 Hz, 2H), 7.00
(d, J=8.6 Hz, 2H), 5.74 (s, 1H), 3.40 (s, 3H); 13C NMR (100 MHz,
CDCl3): δ 164.83(d, J=254 Hz), 164.81, 163.6, 162.8, 132.9, 128.2 (d,
J=3.4 Hz), 128.0 (d, J=9.2 Hz), 119.8, 116.5 (d, J=22 Hz), 114.7,
(Z)-2-Cyano-1-phenylvinyl 4-oxopentanoate (3ap): Yield: 85 mg
114.3, 87.2, 55.7; HRMS: m/z calculated for C17H13 FNO3 [M+H]+
:
1
(70%); H NMR (400 MHz, CDCl3): δ 7.57–7.53 (m, 2H), 7.46–7.39 (m,
298.0879; found: 298.0881
3H), 5.70 (s, 1H), 2.93–2.85 (m, 4H), 2.18 (s, 3H); 13C NMR (100 MHz,
CDCl3): δ 206.2, 169.5, 164.2, 132.0, 131.2, 129.1, 125.8, 114.7, 86.9,
(Z)-2-Cyano-1-(4-nitrophenyl)vinyl 4-methoxybenzoate (3dh):
37.7, 29.7, 27.9; HRMS: m/z calculated for C14H10NO3 [M+H]+
:
Yield: 130 mg (80%); m.p. 109–114 C; H NMR (400 MHz, CDCl3): δ
1
°
244.0974; found: 244.0963.
8.27 (d, J=8.6 Hz, 2H), 8.16 (d, J=8.6 Hz, 2H), 7.72 (d, J=9.1 Hz,
2H), 7.02 (d, J=9.0 Hz, 2H), 5.91 (s, 1H), 3.92 (s, 3H); 13C NMR
(100 MHz, CDCl3): δ 165.1, 162.7, 162.4, 149.5, 137.9, 133.0, 128.7,
126.8, 124.5, 119.3, 114.5, 91.0, 55.8
(Z)-2-Cyano-1-phenylvinyl 1H-indole-2-carboxylate (3aq): Yield:
103.7 mg (72%); m.p. 190–195 C; H NMR (400 MHz, CDCl3): δ 9.14
1
°
(broad, s, 1H), 7.75 (d, J=8.2 Hz, 1H), 7.60–7.57 (m, 3H), 7.51–7.46
(m, 1H), 7.44–7.36 (m, 4H), 7.20 (td, J=7.5, 1.3 Hz, 1H), 5.83 (s, 1H);
13C NMR (100 MHz, CDCl3): δ 163.7, 158.2, 137.9, 132.1, 131.5, 129.2,
127.4, 126.8, 125.7, 124.6, 123.1, 121.5, 114.6, 112.2, 112.1, 87.7;
HRMS: m/z calculated for C18H13N2O2 [M+H]+ : 289.0977; found:
289.0976.
Synthesis of compound 5from 3ab: To a solution of enol ester
3ab (80 mg) in CH3CN (3 ml) at room temperature were added
silver oxide (1 eq.) and DMAP (1.2 eq.). The mixture was stirred for
12 h and then it was concentrated under reduced pressure. The
crude product was purified by column chromatography on silica
gel.
(Z)-2-Cyano-1-phenylvinyl furan-2-carboxylate (3ar): Yield:
81.26 mg (68%); 1H NMR (400 MHz, CDCl3): δ 7.72–7.71 (m, 1H),
7.57–7.52 (m, 2H), 7.50–7.46 (m, 2H), 7.43–7.37 (m, 2H), 6.64–6.62
(m, 1H), 5.81 (s, 1H); 13C NMR (100 MHz, CDCl3): δ 163.4, 154.5,
148.4, 142.4, 132.1, 131.3, 129.2, 125.7, 121.4, 114.5, 112.7, 87.8;
HRMS: m/z calculated for C14H10NO3 [M+H]+ : 240.0661; found:
240.0668.
1-Oxo-3-phenyl-1H-isochromene-4-carbonitrile (5): Yield: 53 mg
(77%); 1H NMR (400 MHz, CDCl3): δ 8.35 (d, J=7.9 Hz, 1H), 8.06–8.10
(m, 2H), 7.91 (m, 2H), 7.64–7.68 (m, 1H), 7.60–7.53 (m, 3H); 13C NMR
(100 MHz, CDCl3): δ 162.9, 159.5, 136.2, 134.1, 132.4, 130.2, 130.1,
130.0, 129.1, 128.5, 124.6, 119.0, 115.2, 90.8; HRMS: m/z calculated
for C16H10 NO2 [M+H]+ : 248.0712; found: 248.0697.
(Z)-2-Cyano-1-(p–tolyl)vinyl benzoate (3ca): Yield: 94.7 mg (72%);
m.p. 97–99 C; H NMR (400 MHz, CDCl3): δ 8.22 (d, J=8.2 Hz, 2H),
Synthesis of compound 6from 3aa: To a solution of (Z)-2-cyano-1-
phenylvinylbenzoate 3aa (63 mg) in toluene (2 ml) was added
1
°
°
7.69 (t, J=7.4 Hz, 1H), 7.54 (t, J=7.6 Hz, 2H), 7.44 (d, J=8.4 Hz, 2H),
DMAP (0.55 eq.). The mixture was heated at 70 C for 16 h.
7.21 (d, J=8.4 Hz, 2H), 5.76 (s, 1H), 2.38 (s, 3H); 13C NMR (100 MHz,
Afterward, the solvent was removed under reduced pressure and
reaction crude was purified by column chromatography to afford 2-
benzoyl-3-oxo-3-phenylpropanenitrile 6.
CDCl3): δ 164.3, HRMS: m/z calculated for C17H14 NO2 [M+H]+
:
264.1025; found: 264.1027.
(Z)-2-Cyano-1-(4-fluorophenyl)vinyl benzoate (3ba): Yield: 92 mg
(69%); m.p. 100–103 C; H NMR (400 MHz, CDCl3): δ 8.21 (dd, J=
8.2, 1.5 Hz, 2H), 7.70 (t, J=7.6 Hz, 1H), 7.58–7.53 (m, 4H), 7.11 (t, J=
8.6 Hz, 2H), 5.75 (s, 1H); 13C NMR(100 MHz, CDCl3): δ 164.93 (d, J=
254 Hz), 163.5, 163.2, 134.7, 130.7, 129.0, 128.1, 128.0, 127.7, 116.63
(d, J=22 Hz), 116.3, 114.6, 114.5, 87.4.
2-Benzoyl-3-oxo-3-phenylpropanenitrile (6): Yield: 53 mg (84%);
1H NMR (400 MHz, CDCl3): 18.31 (bs, 1H), 8.06 (d, J=7.7 Hz, 4H),
7.64 (t, J=7.7 Hz, 2H), δ 7.54 (t, J=7.4 Hz, 4H); 13C NMR (100 MHz,
CDCl3): δ 193.7, 134.0, 133.8, 129.0, 128.7, 118.7, 86.3; HRMS: m/z
calculated for C16H12 NO2 [M+H]+ : 250.0868; found: 250.0861.
1
°
(Z)-2-Cyano-1-(p–tolyl)vinyl 2-iodobenzoate (3cb): Yield: 155.6 mg
(80%); m.p. 99–105 C; H NMR (400 MHz, CDCl3): δ 8.22 (dd, J=7.8,
1.5 Hz, 1H), 8.10 (dd, J=8.2, 1.2 Hz, 1H), 7.54–7.50 (m, 1H), 7.48 (d,
J=8.2 Hz, 2H), 7.28 (dd, J=7.8, 1.8 Hz, 1H), 7.24 (d, J=8.2 Hz, 2H),
5.76 (s, 1H), 2.39 (s, 3H); 13C NMR (100 MHz, CDCl3): δ 164.4, 162.6,
142.9, 142.2, 134.1, 132.2, 130.0, 128.6, 128.5, 125.9, 114.9, 95.3,
1
°
Acknowledgements
The authors would like to thank CSIR, New Delhi and DST-SERB,
New Delhi, India for providing financial grant and IIT Ropar for
infrastructural facilities and fellowship to CK. The authors would
like to thank Dr. C. M. Nagaraja, IIT Ropar for X-ray crystallog-
raphy.
86.5, 21.7; HRMS: m/z calculated for C17H13 I NO2 [M+H]+
389.9991; found: 389.9975.
:
(Z)-2-Cyano-1-(4-fluorophenyl)vinyl 2-iodobenzoate (3bb): Yield:
143 mg (73%); H NMR (400 MHz, CDCl3): δ 8.19 (dd, J=8.1, 1.4 Hz,
1
Eur. J. Org. Chem. 2020, 1–8
www.eurjoc.org
6
© 2020 Wiley-VCH GmbH
��
These are not the final page numbers!

Full Papers
doi.org/10.1002/ejoc.202001369
[12] a) F. Huang, T. D. Quach, R. A. Batey, Org. Lett. 2013, 15, 3150–3153; b) J.
Conflict of Interest
1
2
3
4
5
6
7
8
9
Park, S. H. Han, S. Sharma, S. Han, Y. Shin, N. K. Mishra, J. H. Kwak, C. H.
Lee, J. Lee, I. S. Kim, J. Org. Chem. 2014, 79, 4735–4742; c) S.-L. Zhang, C.
Xiao, H.-X. Wana, X. Zhang, Chem. Commun. 2019, 55, 4099–4102; d) D.
Zhang, J. M. Ready, Org. Lett. 2005, 7, 5681–5683; e) C. Zhang, L. Chen,
K. Chen, C. Wang, Z. Xu, H. Jiang, S. Zhu, Org. Chem. Front. 2018, 5,
2510–2514; f) M. V. Pham, N. Cramer, Angew. Chem. 2014, 126, 14803–
14807; Angew. Chem. Int. Ed. 2014, 53, 14575–14579.
The authors declare no conflict of interest.
Keywords: 2-Alkynylnitrile
Hydrocarboxylation · Z-stereoselectivity
·
[BMIM]OH
·
Enol esters
·
[13] a) R. D. Bach, R. A. Woodard, T. J. Anderson, M. D. Glick, J. Org. Chem.
1982, 47, 3107–3712; b) B. F. Hennionand, D. B. Killian, T. H. Vaughnand,
J. A. Nieuwla, J. Am. Chem. Soc. 1934, 56, 1130–1132; c) G. F.
Hennionand, J. A. Nieuwla, J. Am. Chem. Soc. 1934, 56, 1802–1803;
d) G. F. Hennionand, R. R. Vogt, J. A. Nieuwland, J. Org. Chem. 1936, 01,
159–162; e) P. F. Hudrlik, A. M. Hudrlik, J. Org. Chem. 1973, 38, 4254–
4258; f) P. F. Hudrlik, A. M. Hudrlik, R. J. Rona, R. N. Misra, G. P. Withers, J.
Am. Chem. Soc. 1977, 99, 1993–1996; g) G. A. Krafft, J. A. Katzenellenb-
ogen, J. Am. Chem. Soc. 1981, 103, 5459–5466; h) R. C. Larock, I. K.
Oertle, K. M. Beatty, J. Am. Chem. Soc. 1980, 102, 1966–1974; i) H.
Lamaire, H. J. Lucas, J. Am. Chem. Soc. 1955, 77, 939–945.
[14] a) Y. Wang, Z. Wang, Y. Li, G. Wu, Z. Cao, L. Zhang, Nat. Commun. 2014,
5, 3470; b) U. K. Das, M. Bhattacharjee, J. Organomet. Chem., 2012, 700,
78–82; c) E. Musengimana, C. Fatakanwa, J. Iran. Chem. Soc. 2016, 13,
253–259; d) P. Mamone, M. F. Grünberg, A. Fromm, B. A. Khan, L. J.
Gooßen, Org. Lett. 2012, 14, 3716–3719; e) P. J. González-Liste, S. E.
García- Garrido, V. Cadierno, Org. Biomol. Chem. 2017, 15, 1670–1679;
f) N. E. Leadbeater, K. A. Scott, L. J. Scott, J. Org. Chem. 2000, 65, 3231–
3232.
[15] a) P. Roembke, H. Schmidbaur, S. Cronje, H. Raubenheimer, J. Mol. Catal.
A 2004, 212, 35–42; b) P. J. Gonza’lez-Liste, J. Francos, S. E. García-
Garrido, V. Cadierno, J. Org. Chem. 2017, 82, 1507–1516; c) S. Dupuy, D.
Gasperini, S. P. Nolan, ACS Catal. 2015, 5, 6918; d) B. C. Chary, S. Kim, J.
Org. Chem. 2010, 75, 7928–7931.
[16] a) R. C. Fahey, D. J. Lee, J. Am. Chem. Soc. 1966, 88, 5555–5560; b) B.
Poladura, Á. Martínez-Castañeda, H. Rodríguez-Solla, R. Llavona, C.
Concellón, V. D. Amo, Org. Lett. 2013, 15, 2810–2813; c) T. T. Tidwell,
Angew. Chem. Int. Ed. 2005, 44, 6812–6814; Angew. Chem. 2005, 117,
6973–6975; d) L. Selič, L. Jukić, G. Soršak, S. G. Grdadolnik, B. Stanovnik,
Synth. Commun. 2001, 31, 1743–1752; e) H. Huang, X. Zhang, C. Yu, X.
Li, Y. Zhang, W. Wang, ACS Catal. 2016, 6, 8030–8035.
[1] a) N. Isambert, M. Cruz, M. J. Arévalo, E. Gómez, R. Lavilla, Org. Lett.
2007, 21, 4199–4202; b) R. M. Risi, A. M. Maza, S. D. J. Burke, J. Org.
Chem. 2014, 80, 204–216; c) K. Matsumoto, C. Feng, S. Handa, T. Oguma,
T. Katsuki, Tetrahedron 2011, 67, 6474–6478; d) P. Ilankumaran, J. G.
Verkade, J. Org. Chem. 1999, 64, 9063–9066; e) Y. Ishii, M. Takeno, Y.
Kawasaki, A. Muromachi, Y. Nishiyama, S. Sakaguchi, J. Org. Chem. 1996,
61, 3088–3092; f) Y. Nishimoto, Y. Onishi, M. Yasuda, A. Baba, Angew.
Chem. Int. Ed. 2009, 121, 9131–9134; g) T. Hering, D. P. Hari, B. König, J.
Org. Chem. 2012, 77, 10347–10352; h) S. Vasudevan, C. P. Brock, D. S.
Watt, J. Org. Chem. 1994, 59, 4677–4679; i) N. Panda, P. Mishra, I. Mattan,
J. Org. Chem. 2016, 81, 1047–1056; j) Y. Masuyama, Y. Kobayashi, Y.
Kurusu, J. Chem. Soc. Chem. Commun. 1994, 24, 1123; k) S. C. Bourque, F.
Maltais, W.-J. Xiao, O. Tardif, H. Alper, P. Arya, L. E. Manzer, J. Am. Chem.
Soc. 1999, 121, 3035–3038; l) K. D. Otley, J. A. Ellman, Org. Lett. 2015, 17,
1332–1335; m) F. Simal, A. Demonceau, A. F. Noels, Angew. Chem. Int.
Ed. 1999, 38, 538–540; Angew. Chem. 1999, 111, 559–562.
[2] a) J. Francos, V. Cadierno, Catalysts 2017, 7, 328; b) C. Bruneau, P. H.
Dixneuf, Angew. Chem. Int. Ed. 2006, 45, 2176–2203; Angew. Chem.
2006, 118, 2232–2260; c) F. Alonso, I. P. Beletskaya, M. Yus, Chem. Rev.
2004, 104, 3079–3159; d) P. J. González-Liste, J. Francosz, S. E. García-
Garrido, V. Cadierno, Arkivoc 2018, ii, 17–39.
[3] a) C. Ruppin, P. H. Dixneuf, Tetrahedron Lett. 1986, 27, 6323–6324; b) M.
Kawatsura, J. Namioka, K. Kajita, M. Yamamoto, H. Tsuji, T. Itoh, Org. Lett.
2011, 13, 3285–3287; c) M. Rotem, Y. Shvo, J. Organomet. Chem. 1993,
448, 189–204; d) M. Rotem, Y. Shvo, Organometallics 1983, 2, 1689–
1691; e) J. Jeschke, T. B. Engelhardt, H. Lang, Eur. J. Org. Chem. 2016,
1548–1554; f) S. Karabulut, B. Ö. Öztürk, Y. Ìmamoğlu, J. Organomet.
Chem. 2010, 695, 2161–2166; g) S. Saha, T. Ghatak, B. Saha, H. Doucet,
J. K. Bera, Organometallics 2012, 31, 5500–5505.
[4] a) J. Jeschke, C. Gabler, H. Lang, J. Org. Chem. 2016, 81, 476–484; b) H.
Doucet, B. Martin-Vaca, C. Bruneau, P. H. Dixneuf, J. Org. Chem. 1995, 60,
7247–7255; c) M. Nishiumi, H. Miura, K. Wada, S. Hosokawa, M. Inoue,
ACS Catal. 2012, 2, 1753–1759; d) M. J. Stark, D. T. Tang, N. P. Rath, E. B.
Bauer, Tetrahedron Lett. 2018, 59, 873–877; e) L. J. Goossen, J. Paetzold,
D. Koley, Chem. Commun. 2003, 706–707; f) M. Nishiumi, H. Miura, K.
Wada, S. Hosokawa, M. Inoue, Adv. Synth. Catal. 2010, 352, 3045–3052;
g) C. S. Yi, R. Gao, Organometallics 2009, 28, 6585–6592; h) K. Cheung,
W. Wong, M. So, Z. Zhou, S. Yan, K. Wong, Chem. Commun. 2013, 49,
710–712.
[5] a) D. L. Smith, W. R. F. Goundry, H. W. Lam, Chem. Commun. 2012, 48,
1505–1507; b) Q. Zhang, X. Lu, X. Han, J. Org. Chem. 2001, 66, 7676–
7684; c) J. Wu, X. Deng, H. Hirao, N. J. Yoshikai, J. Am. Chem. Soc. 2016,
138, 9105–9108; d) T. Wakabayashi, Y. Ishii, T. Murata, Y. Mizobe, M.
Hidai, Tetrahedron Lett. 1995, 36, 5585–5588; e) N. Tsukada, A.
Takahashi, Y. Inoue, Tetrahedron Lett. 2011, 52, 248–250.
[6] a) M. J. Christopher, S. Kalberg, A. Pizzano, J. Am. Chem. Soc. 1998, 120,
4345–4353; b) A. Lumbroso, N. R. Vautravers, B. Breit, Org. Lett. 2010, 12,
5498–5501; c) C. Bianchini, A. Meli, M. Peruzzini, F. Zanobini, Organo-
metallics 1990, 9, 1155–1160; d) S. Ganss, J. Pedroni, A. Lumbroso, G.
Leonhardt-Lutterbeck, A. Meißner, S. Wei, H.-J. Drexler, D. Heller, B. Breit,
Org. Synth. 2016, 93, 367–384.
[7] a) H. Nakagawa, Y. Okimoto, S. Sakaguchi, Y. Ishii, Tetrahedron Lett.
2003, 44, 103–106; b) J. S. Merola, F. T. Ladipo, Polyhedron 2014, 70,
125–132; c) L. Zeng, R. Chen, C. Zhang, H. Xie, S. Cui, Chem. Commun.
2020, 56, 3093–3096.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
[17] Some [BMIM]OH catalyzed organic synthesis: a) L. Gu, W. Wang, J. Liu,
G. Lia, M. Yuan, Green Chem. 2016, 18, 2604–2608; b) B. C. Ranu, S.
Banerjee, Org. Lett. 2005, 7, 3049–3052; c) H. Zang, M. Wang, B.-W.
Cheng, J. Song, Ultrason. Sonochem., 2009, 16, 301–303; d) M. A.
Waseem, A. Shireen, A. Srivastava, Rahila, I. R. Siddiqui, Tetrahedron Lett.
2014, 55, 6072–6076.
[18] T. S. Mansour, Tetrahedron Lett. 1988, 29, 3437–3440.
[19] Deposition Numbers 1955826 (for 3aa), 1956366 (for 3ab), 1956367 (for
3ah), 1955829 (for 3al), 1955825 (for 3ch), 1955831 (for 3am), 1955836
(for 3aq), 1955838 (for 3ai), and 1955847 (for 3aj) contain the
supplementary crystallographic data for this paper. These data are
provided free of charge by the joint Cambridge Crystallographic Data
Centre and Fachinformationszentrum Karlsruhe Access Structures
service www.ccdc.cam.ac.uk/structures.
[20] a) J.-M. Xu, B.-K. Liu, W.-B. Wu, C. Qian, Q. Wu, X.-F. Lin, J. Org. Chem.
2006, 71, 3991–3993; b) B. C. Ranu, S. Banerjee, Org. Lett. 2005, 7, 3049–
3052.
[21] a) A. Saddiqa, M. Usman, O. C. Akmak, Turk. J. Chem. 2017, 41, 153–178;
b) A. Simon, R. W. Dunlop, E. L. Ghisalberti, K. Sivasithamparam, Soil Biol.
Biochem. 1988, 20, 263–264; c) J. V. N. Vara Prasad, K. S. Para, E. A.
Lunney, D. F. Ortwine, J. B. Dunbar, D. Ferguson, P. J. Tummino, D.
Hupe, B. D. Tait, J. M. Domagala, C. Humblet, T. N. Bhat, B. Liu, D. M. A.
Guerin, E. T. Baldwin, J. W. Erickson, T. K. Sawyer, J. Am. Chem. Soc. 1994,
116, 6989–6990; d) L. Pochet, R. Frédérick, B. Masereel, Curr. Pharm. Des.
2004, 10, 3781–3796; e) Y. Soltani, L. C. Wilkins, R. L. Melen, Synlett 2018,
29, 1–7.
[22] Y. Li, D. Shi, P. Zhu, H. Jin, S. Li, F. Mao, W. Shi, Tetrahedron Lett. 2015,
56, 390–392.
[8] J. F. Chen, C. K. Li, Org. Lett. 2018, 20, 6719–6724.
[9] R. Hua, X. Tian, J. Org. Chem. 2004, 69, 5782–5784.
[10] a) Y. Ishino, I. Nishiguchi, S. Nakap, T. Hirashima, Chem. Lett. 1981, 5,
641–644; b) N. Kikui, T. Hinoue, Y. Usuki, T. Satoh, Chem. Lett. 2018, 47,
141–143.
Manuscript received: October 13, 2020
Revised manuscript received: November 11, 2020
Accepted manuscript online: November 24, 2020
[11] C. Schaefer, G. C. Fu, Angew. Chem. Int. Ed. 2005, 44, 4606–4608; Angew.
Chem. 2005, 117, 4682–4684.
Eur. J. Org. Chem. 2020, 1–8
www.eurjoc.org
7
© 2020 Wiley-VCH GmbH
��
These are not the final page numbers!

FULL PAPERS
1
2
3
4
C. Kumari, Dr. A. Goswami*
5
1 – 8
6
7
8
9
A Facile Transition Metal-Free
Ionic Liquid [BMIM]OH Mediated
Regio- and Stereoselective Hydro-
carboxylation of Alkynylnitriles
An atom economical and transition
metal-free, green methodology for
the synthesis of nitrile substituted Z-
enol esters via ionic liquid [BMIM]OH
mediated hydrocarboxylation of alky-
nylnitriles is reported.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57