Cyanides-free cyanation of aryl halides using formamide

Article abstract of DOI:10.1002/adsc.201000807

A novel method for cyanation of aryl halides using formamide as a non-toxic cyanide source is reported. It is a single-step, solvent-free method wherein formamide itself acts as solvent as well as source of cyanide in the presence of phosphorus oxychloride and palladium acetate/xantphos catalyst. Aryl iodides as well as aryl bromides provided moderate to excellent yields of up to 93%. Copyright

Full text of DOI:10.1002/adsc.201000807

UPDATES
DOI: 10.1002/adsc.201000807
Cyanides-Free Cyanation of Aryl Halides using Formamide
a
a
a
a
Dinesh N. Sawant, Yogesh S. Wagh, Pawan J. Tambade, Kushal D. Bhatte,
a,
and Bhalchandra M. Bhanage *
Department of Chemistry, Institute of Chemical Technology (Deemed University), N. Parekh Marg, Matunga, Mumbai –
00019, India
a
4
Fax : (+91)-222-414-5614; phone: (+91)-222-414-5616; e-mail: bm.bhanage@ictmumbai.edu.in or
bhalchandra_bhanage@yahoo.com
Received: October 26, 2010; Revised: December 29, 2010; Published online: March 10, 2011
Supporting information for this article is available on the WWW under
http://dx.doi.org/10.1002/adsc.201000807.
[
11]
[12]
Abstract: A novel method for cyanation of aryl hal-
ides using formamide as a non-toxic cyanide source
is reported. It is a single-step, solvent-free method
wherein formamide itself acts as solvent as well as
source of cyanide in the presence of phosphorus
oxychloride and palladium acetate/xantphos cata-
lyst. Aryl iodides as well as aryl bromides provided
moderate to excellent yields of up to 93%.
cyanide,
acetone cyanohydrins,
etc., restricting
their applications. A synthesis of nitriles using milder
reagents like K [Fe(CN) ] has also been reported.
Although K [Fe(CN) ] is easy to handle, it should be
noted that it is also derived from a conventional
metal cyanide source. Recently, N-cyanobenzimida-
zole was also used as cyanide source for aryl hal-
[
13]
4
6
4
6
[
14]
ides.
however, it requires drastic reaction condi-
tions, use of Grignard reagents and the preparation of
cyanoimidazole using bromocyanogen which is a toxic
cyanide source, so limiting its application.
Keywords: aryl halides; CÀC coupling; cyanation;
formamide; nitriles; palladium
Considering these issues, we focused our attention
towards the development of a novel cyanide-free pro-
tocol for the synthesis of nitriles. Herein, we report a
simple, non-toxic, efficient and cyanide-free, single-
step protocol for the cyanation of aryl halides using
formamide as a cyanide source. It was observed that
Introduction
Cyanation is an important tool for the introduction of amides can be synthesized from aryl halides using a
various functionalities such as carboxylic acids, alde- strategy of CO-free aminocarbonylation via reaction
[
15]
hydes, ketones, oximes, amides, amines, azoles, and of dimethylformamide (DMF).
oxazolidines in aromatic and heteroaromatic rings.
We planned to
[
1]
extend this concept further for nitrile synthesis for the
Hence, aryl nitriles have great industrial importance first time wherein formamide can be replace the
for the synthesis of chemicals, dyes, natural products, DMF and with a suitable catalyst it can be converted
[
2]
therapeutic drugs and their intermediates. Cyana- to nitriles (see Scheme 1).
tion of aryl halides is the most common method used
for the synthesis of aryl nitriles. The Rosenmund–von
[3]
[4]
Braun and Sandmeyer reactions are most tradi- Results and Discussion
tional methods used for cyanation of aryl halides,
which require stoichiometric amounts of toxic CuCN The synthesis of benzonitrile (3a) from formamide
and harsh reaction conditions. Recent developments (2a) and iodobenzene (1a) using Pd CAHTUNGTERNNNU(G OAC) /dppf as
2
in the transition metal-catalyzed methodologies for catalytic system and POCl as an additive was investi-
3
the preparation of aryl nitriles from aryl halide has gated. It has been observed that benzonitrile was
[
5]
changed the scenario and for which many palladi- formed as a single product (38%) along with unreact-
um-, copper-, or nickel-catalyzed cyanation protocols ed iodobenzene (Table 1, entry 5). Based on these
[
6]
have been explored. Among these, palladium was preliminary results, the reaction parameters for the
widely investigated for the cyanation of aryl halides. cyanation reaction were optimized. Test experiments
Most of these protocols requires highly toxic and en- to check the roles of every component in reaction
vironmentally hazardous cyanide sources such as system were performed (Table 1). They show that
[7]
[8]
[9]
[10]
KCN, NaCN, CuCN, Zn(CN)2,
trimethylsilyl
Adv. Synth. Catal. 2011, 353, 781 – 787
ꢀ 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
781

Dinesh N. Sawant et al.
UPDATES
Scheme 1. Cyanides-free cyanation of aryl halides using formamide.
Table 1. Test experiment for cyanides-free cyanation of iodo-
It was observed that Pd ACHTUNGETRNN(UNG OAc) provided higher
2
[a]
benzene (1a) with formamide (2a).
yields than other palladium precursors (Table 2, en-
tries 1, 7 and 8). The yield was increased with the re-
action temperature range from 130–1508C, in which
1
408C reflects to be optimum temperature (Table 2,
entries 9–13). The reaction time was also optimized
Table 2, entries 14–17) and a maximum yield of prod-
uct 3a, that is, 89% yield was obtained after 48 h
Table 2, entry 16). The effect of catalyst loading
(
[b]
Entry Pd
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
(OAc)
L2 POCl3 1a 2a Yield [%]
2
(
1
2
3
4
5
–
–
3
3
3
–
3
3
3
3
3
3
3
3
3
3
3
3
3
0
0
ranging from 1–7 mol% of substrate for the model re-
action was studied and it was observed that increasing
the catalyst loading from 1 mol% to 5 mol% led to a
remarkable increase in the yield of the desired prod-
uct (Table 3, entries 1–5). Furthermore, we also inves-
tigated the effect of the metal to ligand ratio, whereby
a 1:2 ratio was found to be optimal (Table 3, entry 3).
3
–
3
3
traces
0
38
–
3
[
a]
À1
Reaction conditions: 1a (1.0 mmol), 2a (10 mLmmol ),
Pd(OAc) (5 mol%), L2 (10 mol%), POCl (2.0 mmol),
208C, 24 h under nitrogen atmosphere.
GC yield.
ACHTUNGTRENNUNG
2
3
1
A brief survey of the POCl concentration effect
[
b]
3
was also performed and optimal results were achieved
using 2 equivalents of POCl (Table 4, entries 1–5).
3
Pd
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
(OAC) , dppf and POCl were all necessary for the
Studies on the effect of the formamide concentra-
tion revealed that 8–10 mLmmol formamide are es-
2
3
À1
title reaction (Table 1, entries 1–5).
Various bidentate phosphine ligands as shown in sential for higher yields of the desired product
Figure 1 were investigated for the cynation reaction (Table 5, entries 4 and 5).
(
Table 2). The best result was obtained with Xantphos
Thus, the optimized reaction conditions are iodo-
(OAc) (0.05 mmol), Xant-
ligand (54%, Table 2, entry 1) while most of the other benzene (1a, 1 mmol), PdAHCTNUGTRENNNUG
2
ligands were found to be ineffective (Table 2, en- phos (0.10 mmol) and POCl (2 mmol) in formamide
3
À1
tries 3–6).
(2a, 10 mLmmol of iodobenzene) at 1408C for 48 h.
Figure 1. Structures of the ligands L1–L6.
782
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ꢀ 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Adv. Synth. Catal. 2011, 353, 781 – 787

Cyanides-Free Cyanation of Aryl Halides using Formamide
Table 2. Optimization for the cyanides-free cyanation reac-
tion of iodobenzene (1a) with formamide (2a).
Table 4. Influence of POCl concentration on cyanides-free
cyanation.
3
[a]
[a]
[b]
Entry
POCl (mmol)
Yield of 3a [%]
3
1
2
3
4
5
0.5
1.0
1.5
2.0
2.5
42
69
76
87
88
Entry Ligand Pd cata-
lyst
Temp.
[8C]
Time
[h]
Yield
[b]
[%]
[a]
À1
Reaction conditions: 1a (1.0 mmol), 2a (10 mLmmol ),
Pd(OAc) (5 mol%), L1 (10 mol%), POCl , 1408C, 48 h,
under nitrogen.
Effect of ligand
ACHTUNGTRENNUNG
2
3
1
2
3
4
5
6
L1
L2
L3
L4
L5
L6
Pd
Pd(OAc) 120
Pd(OAc) 120
Pd(OAc) 120
Pd(OAc) 120
Pd(OAc) 120
A
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
C
H
T
U
N
G
T
R
E
N
N
U
N
G
(OAc) 120
24
24
24
24
24
24
54
40
0
0
0
2
[b]
2
GC yield.
2
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
2
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
Table 5. Influence of formamide concentration on cyanides-
[a]
2
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
0
free cyanation.
2
Effect of metal precursor
[
b]
Entry
Formamide (mL)
Yield of 3a [%]
7
8
L1
L1
PdCl2
120
24
24
42
26
Pd(acac) 120
ACHTUNGTRENNUNG
2
1
2
3
4
5
2
4
6
8
20
65
82
87
91
Effect of temprature
9
1
1
1
1
L1
L1
L1
L1
L1
Pd
Pd(OAc) 135
Pd(OAc) 140
Pd(OAc) 145
Pd(OAc) 150
A
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
C
H
T
U
N
G
T
R
E
N
N
U
N
G
(OAc) 130
24
24
24
24
24
57
61
69
70
71
2
0
1
2
3
2
2
10
2
[a]
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
Reaction conditions: 1a (1.0 mmol), 2a, Pd ACHTUNREGTNNUNG( OAc) (5
2
mol%), L1 (Xantphos) (10 mol%), POCl3 (2.0 mmol),
1408C, 48 h, under nitrogen.
2
Effect of time
1
1
1
1
4
5
6
7
L1
L1
L1
L1
Pd
Pd(OAc) 140
Pd(OAc) 140
Pd(OAc) 140
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
(OAc) 140
36
42
48
54
77
81
89
91
2
[b]
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
GC yield.
2
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
2
2
these conditions. It was observed that ortho-substitut-
ed substrates are well tolerated providing excellent
yields of desired products (Table 6, entries 4 and 5).
Iodonaphthalene provided the highest yield 93% of
the expected product (Table 6, entry 6), while b-sub-
stitution of a methoxy group in 1-iodonapthalene led
to a decrease in yield (Table 6, entry 7). The method
is also useful for the preparation of heterocyclic ni-
triles. Heterocyclic iodides such as 2-iodothiophene,
5-iodoindole also gave good yields (Table 6, entries 8
and 9). It is noteworthy to mention that the present
methodology was successfully applied to aryl bro-
mides which are known to be difficult substrates and
it delivered moderate yield in range of 49–66% of
yield.
[
a]
À1
Reaction conditions: 1a (1.0 mmol), 2a (10 mLmmol ),
Pd precursor (5 mol%), ligand (10 mol%), POCl3
(
2.0 mmol), under nitrogen.
[
b]
GC yield.
Table 3. Influence of catalyst loading on cyanides-free cyan-
[a]
ation.
Entry Pd ACHTUNGTRENNUNG( OAc) (mol%) L1 (mol%) Yield of 3a [%]
2
[
b]
1
2
3
4
5
1
2.5
5
5
7
2
5
10
5
14
42
68
89
72
90
They showed the same pattern of reactivity as was
observed for aryl iodides, that is, electron-rich aryl
bromides giving good yields (Table 6, entries 10–12).
ortho-Substituted aryl bromides give moderate yields
[
a]
À1
Reaction conditions: 1a (1.0 mmol), 2a (10 mLmmol ),
Pd(OAc) , L1, POCl (2.0 mmol), 1408C, 48 h, under ni-
trogen.
ACHTUNGTRENNUNG
2
3
[
b]
GC yield.
(
Table 6, entries 13 and 14) and 1-bromonapthalene
gives the maximum yield of the expected product
In order to study the scope and generality of the (Table 6, entry 15). To our surprise, when diiodoben-
present protocol, different types of aryl halides con- zene was treated with formamide under the same con-
taining electron-donating groups were reacted with ditions phthalimide was obtained as a product instead
formamide and they gave good to excellent yields of of dinitrile (Table 6, entry 16). To the best of our
the desired product (Table 6). We found that different knowledge this is the first example of a CO-free syn-
aryl halides such as aryl bromides, aryl iodides were thesis of phthalimide from diiodobenzene. Aryl chlor-
converted to the corresponding aryl nitriles under ides were found to be ineffective for this reaction. It
Adv. Synth. Catal. 2011, 353, 781 – 787
ꢀ 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
asc.wiley-vch.de
783

Dinesh N. Sawant et al.
UPDATES
Table 6. Scope of cyanides-free cyanation of aryl halides is worthy of note that the reaction also produces a
[a]
using formamide (2a).
stoichiometric amount of salt as a by-product after re-
action because of POCl3.
Mechanism
To probe the mechanism of the studied transforma-
tion, the reaction of iodobenzene was performed with
DMF instead of formamide under the same reaction
conditions wherein the aminocarbonylated product
was obtained instead of the expected benzonitrile
[b]
Entry Aryl halide
Product
Yield [%]
3a 81
1
2
3
(
Scheme 2). As DMF does not have a free hydrogen
3b 89
3c 84
4
5
3d 87
3e 91
Scheme 2. Reaction of iodobenzene with DMF to predict
the possible mechanism.
6
7
3f 93
3g 78
it did not undergo dehydration giving the aminocar-
bonylated product. This is a major difference in our
work and previous work reported by Hiyama and co-
[
15a]
workers
and they did not observe nitriles in the
case of formamide probably due to a lack of the right
catalyst. On the grounds of results obtained, we
assume that the reaction of formamide with iodoben-
zene might be involving benzamide as an intermedi-
ate which on dehydration could give benzonitrile. In a
substrate study it was observed that diiodobenzene
gave pthalamide instead of the nitrile (Table 6,
entry 14) which also supports the hypothesis, that is,
the reaction involves aminocarbonylation, therefore
as soon as amide is formed it prefers cyclization in-
stead of dehydration and forms phthalimide.
8
9
3h 59
3i 67
1
1
1
0
1
2
3a 49
3b 56
3c 53
From the previous report on CO-free aminocarbo-
[
15]
nylation and the results obtained, we predict that
our nitrile synthesis involves oxidative insertion of Pd
into the CÀX bond which produces an aryl palladium
1
1
3
4
3d 50
3e 57
halide intermediate 1 (Scheme 3). Thereafter, an im-
minium salt (Vilsmeier-type reagent) undergoes nu-
cleophilic addition of the aryl palladium halide to
form 3, which then undergoes b-hydride elimination
forming intermediate 4, which is a key intermediate
of the reaction. In case of formamide, intermediate 4
undergoes aminocarbonylation followed by dehydra-
tion to give nitriles, while in the case of the DMF re-
action it gives an aminocarbonylated product as there
1
1
5
6
3f 66
6a 72
is no free hydrogen. As earlier reported by Hosoi
[
a]
À1
[15a]
Reaction conditions: 1 (1.0 mmol), 2a (10 mLmmol ), et al.
Pd
1408C, 48 h under nitrogen.
b]
the formation of Vilsmeier reagent in this
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
(OAc) (5 mol%), L1 (10 mol%), POCl (2.0 mmol), case is essential for the reaction to occur and no base
2
3
is employed to regenerate Pd(0) from the hydro palla-
[
Yield of isolated product after column chromatography.
[15a]
dium halide species (HÀPdÀX).
784
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Adv. Synth. Catal. 2011, 353, 781 – 787

Cyanides-Free Cyanation of Aryl Halides using Formamide
Scheme 3. Proposed mechanism for the cyanation.
Conclusions
Elmer). GC analysis was carried out on Perkin–Elmer
Clarus-400) gas chromatography equipped with flame ioni-
zation detector with a capillary column (Elite-1, 30 mꢁ
.32 mmꢁ0.25 mm).
(
In summary, we have reported a novel, non-toxic and
convenient methodology for the cyanation of aryl hal-
ides using formamide as cyanide source. The process
0
is a one-step reaction where no extra solvent is re- General Experimental Procedure for Cyanide-Free
quired as formamide acts as solvent as well as source Cynation Reactions
of cyanide. These advantages thus suggest that the de-
A mixture of aryl halide (1 mmol), Pd ACHTUNGTERNNGN(U OAc) (5 mol%) and
2
veloped protocol might prove to be an attractive al-
ternative to the reported methods for nitrile synthesis.
Further applications of protocol and studies on the
CO-free synthesis of phthalimide are under progress.
À1
Xantphos (10 mol%) in formamide (10 mLmmol ) was
placed in a 25-mL two-necked round-bottom flask equipped
with a condenser at room temperature under nitrogen. Then
POCl (2 mmol) was added to the reaction mixture which
3
was placed in an oil bath and magnetically stirred at 1408C
for 48 h under complete nitrogen atmosphere. After comple-
tion, the reaction mixture was cooled to room temperature
and was poured into a saturated solution of NaHCO3
Experimental Section
(
2
50 mL). The product was extracted with diethyl ether (4ꢁ
0 mL). The combined organic layers were dried over
Na SO and evaporated to afford the crude product which
Materials and Methods
2
4
All the chemicals were purchased from Sigma Aldrich, Lan-
caster (Alfa-Aesar), S. D. fine chemical and commercial sup-
pliers. All reactions were carried out under a nitrogen at-
mosphere. The progress of the reaction was monitored by
thin layer chromatography using Merck silica gel 60 F254
plates. The product was visualized with a 254 nm UV lamp.
Products were purified by column chromatography on silica
gel (60–120) mesh. All yields reported in Table 6 (entries 1–
was then purified by column chromatography on silica gel
using petroleum ether/diethyl ether or petroleum ether/
(
ethyl acetate combination) to afford the pure product. The
products are well known and were confirmed by IR, GC-
MS, H and C NMR spectroscopic analysis.
1
13
General Experimental Procedure for Test
Experiments
1
6) refer to isolated yields of pure compounds as deter-
1
mined by H NMR while yields reported in Table 1–Table 5
are GC yields. All products are well known compounds and
identified by H NMR, C NMR, GC-MS, FT-IR data that
A mixture of iodobenzene (1 mmol), Pd ACHTUNGTERNN(UNG OAc) (5 mol%)
2
1
13
À1
and Xantphos (10 mol%) in DMF (10 mLmmol ) was
placed in a 25-mL two-necked round-bottom flask equipped
with a condenser at room temperature under nitrogen. Then
1
were compared with previously reported data. H NMR and
13
C NMR spectra were recorded with a JEOL FT-NMR,
Model-AL300 (300 MHz) spectrometer in CDCl . Chemical
POCl (2 mmol) was added to the reaction mixture which
3
3
shifts are reported in parts per million (d) relative to teta-
methylsilane as internal standard. J (coupling constants) are
reported in Hz, splitting patterns of proton are described as
s (singlet), d (doublet), t (triplet), m (multiplet). Mass spec-
tra were obtained on a Shimadzu GCMS-QP 2010 instru-
ment. The IR spectra were recorded with FT-IR (Perkin–
was placed in oil bath with magnetical stirring at 1408C for
48 h under complete nitrogen atmosphere. After comple-
tion, the reaction mixture was cooled to room temperature
and was poured into a saturated solution of NaHCO3
(50 mL). The product was extracted with diethyl ether (4ꢁ
20 mL). The combined organic layers were dried over
Adv. Synth. Catal. 2011, 353, 781 – 787
ꢀ 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
asc.wiley-vch.de
785

Dinesh N. Sawant et al.
UPDATES
Na SO and evaporated to afford the crude product which
d 137.8, 131.8, 128, 114.6, 110.2; GC-MS (EI, 70 eV): m/z
(%)=109 (M , 100), 82 (10), 58 (34), 57 (9), 45 (31).
2
4
+
was purified by column chromatography on silica gel (using
petroleum ether/diethyl ether or petroleum ether/ethyl ace-
tate combination) to afford the pure product. The product
5-Cyanoindole (3i) (Table 6, entry 9): Yellowish solid;
1
H NMR (300 MHz, CDCl , 258C): d=8.60 (bs, 1H), 8.0 (s,
3
1
13
was confirmed by IR, GC-MS, H and C NMR spectro-
scopic analysis.
1H), 7.47 (d, J=8.8 Hz, 1H,), 7.42 (dd, J=1.2, 8.8 Hz, 1H),
13
7.34 (t, J=2.8 Hz, 1H), 6.64–6.63 (m, 1H); C NMR
(75 MHz, CDCl , 258C): d=137.6, 127.7, 126.8, 126.4, 124.7,
Benzonitrile (3a) (Table 6, entries 1 and 10): Colourless
3
1
liquid; H NMR (300 MHz, CDCl , 258C): d=7.67–7.58 (m,
121.1, 112.2, 103.2, 102.3; GC-MS (EI, 70 eV): m/z (%)=
3
1
3
+
3
H), 7.50–7.45 (m, 2H); C NMR (75 MHz, CDCl , 258C):
142 (M , 100), 115 (39), 114 (18), 88 (11).
3
d=132.5, 131.7, 128.8, 118.5, 111.9; GC-MS (EI, 70 eV): m/z
Phthalimide (6a) (Table 6, entry 16): White solid;
+
1
(
(
%)=103 (M , 100), 76 (41), 50 (13); IR (neat): n=2228
H NMR (300 MHz, CDCl
(bs, 1H); C NMR (75 MHz, CDCl
132.6, 122.9; GC-MS (EI, 70 eV): m/z (%)=147 (M , 100),
3
, 258C): d=7.81 (s, 4H), 11.33
À1
13
CꢀN), 1598, 1490, 1447, 757, 687, 547 cm .
, 258C): d=169.2, 134.2,
3
+
4
-Methoxybenzonitrile (3b) (Table 6, entries 2 and 11):
1
1
04 (58), 76 (54), 50 (21).
White solid; H NMR (400 MHz, CDCl , 258C): d=7.55 (d,
3
N,N-Dimethylbenzamide (5a) (Scheme 2): Yellowish
J=8.7 Hz, 2H), 6.92 (d, J=8.7 Hz, 2H), 3.83 (s, 3H);
1
1
3
solid; H NMR (300 MHz, CDCl , 258C): d=2.9 (s, 3H), 3.1
C NMR (75 MHz, CDCl , 258C): d=162.8, 133.9, 119.2,
3
3
1
3
+
(
s, 3H), 7.4 (s, 5H); C NMR (75 MHz, CDCl , 258C): d=
1
1
14.7, 103.8, 55.5; GC-MS (EI, 70 eV): m/z (%)=133 (M ,
00), 103 (46), 90 (45), 76 (12), 63 (16); IR (neat): n=2219
3
1
7
5
71.7, 136.4, 129.6, 128.4, 127.1, 39.6, 35.4; GC-MS (EI,
0 eV): m/z (%)=149 (28), 148 (61), 105 (M , 100), 77 (61),
1 (18).
+
(
5
CꢀN), 1605, 1675, 1509, 1462, 1259, 1176, 1023, 828, 683,
À1
46 cm .
4
-Methylbenzonitrile (3c) (Table 6, entries 3 and 12): Col-
1
ourless liquid; H NMR (400 MHz, CDCl , 258C): d=7.53
3
(
d, J=8.3 Hz, 2H), 7.26 (d, J=8.3 Hz, 2H), 2.42 (s, 3H);
13
C NMR (75 MHz, CDCl , 258C): d=143.5, 131.7, 129.6,
3
+
Acknowledgements
1
1
(
18.9, 109, 21.6; GC-MS (EI, 70 eV): m/z (%)=117 (M ,
00), 116 (61), 90 (44), 89 (26), 63 (13); IR (neat): n=2228
À1
The authors are grateful to the University Grant Commission,
India for financial support under Green Technology Centre
of Institute of Chemical Technology.
CꢀN), 1607, 1508, 816, 546 cm .
2
-Methylbenzonitrile (3d) (Table 6, entries 4 and 13): Yel-
1
lowish liquid; H NMR (400 MHz, CDCl , 258C): d=7.60–
7
3
1
3
.45 (m, 2H), 7.26–7.32 (m, 2H), 2.55 (s, 3H); C NMR
(
1
75 MHz, CDCl , 258C): d=142, 132.7, 132.5, 130.2, 126.2,
19.1, 112.8, 20.5; GC-MS (EI, 70 eV): m/z (%)=117 (M ,
3
+
References
1
00), 116 (53), 90 (54), 89 (31), 63 (13); IR (neat): n=2226
À1
(
CꢀN), 1606, 1487, 762 cm .
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-Methoxybenzonitrile (3e) (Table 6, entries 5 and 14):
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Light yellow solid; H NMR (400 MHz, CDCl , 258C): d=
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7
.57–7.52 (m, 2H), 7.03–6.97 (m, 2H), 3.92 (s, 3H);
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C NMR (75 MHz, CDCl , 258C): d=161.7, 134.4, 133.6,
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1
165, 1112, 1020, 811, 755, 729 cm .
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-Cyanonaphthalene (3f) (Table 6, entries 6 and 15):
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White solid; H NMR (300 MHz, CDCl , 258C): d=8.22 (d,
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1
1
1
7
.70–7.48 (m, 3H); C NMR (75 MHz, CDCl , 258C): d=
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33.3, 132.9, 132.6, 132.4, 128.7, 128.6, 127.6, 125.1, 124.9,
+
17.9, 110.2; GC-MS (EI, 70 eV): m/z (%)=153 (M , 100),
26 (21), 76 (8), 63 (10); IR (neat): n=2222 (CꢀN), 800,
À1
71 cm .
1
-Cyano-2-methoxynaphthalene (3g) (Table 6, entry 7):
1
White solid; H NMR (300 MHz, CDCl , 258C): d=8.02–
3
8
.10 (m, 2H), 7.83 (d, J=8.4 Hz, 1H), 7.64 (t, J=7.3,
.6 Hz, 1H), 7.45 (t, J=7.33, 7.6 Hz, 1H), 7.27 (d, J=9 Hz);
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(
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3
1
1
H), 7.49–7.66 (m, 2H); C NMR (75 MHz, CDCl , 258C):
3
786
asc.wiley-vch.de
ꢀ 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Adv. Synth. Catal. 2011, 353, 781 – 787

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787