Synthesis of α-aryl nitriles through B(C6F5)3-catalyzed direct cyanation of α-aryl alcohols and thiols

Article abstract of DOI:10.1016/j.tet.2009.03.073

Various α-aryl nitriles have been prepared in excellent yield from the corresponding α-aryl alcohols employing 3 mol % of B(C₆F₅)₃ (1) as Lewis acid catalyst and (CH₃)₃SiCN (TMSCN) as cyanide source. Cyano transfer from TMSCN to alcohol proceeds within short reaction time at rt. α-Aryl thiols also produce corresponding nitriles in good to excellent yield at reflux condition.

Full text of DOI:10.1016/j.tet.2009.03.073

Tetrahedron 65 (2009) 4351–4355
Contents lists available at ScienceDirect
Tetrahedron
journal homepage: www.elsevier.com/locate/tet
Synthesis of
a
-aryl nitriles through B(C6F5)3-catalyzed direct cyanation
of
a-aryl alcohols and thiols
y
*
Gurusamy Rajagopal , Sung Soo Kim
Department of Chemistry, Inha University, Incheon 402-751, South Korea
a r t i c l e i n f o
a b s t r a c t
Article history:
Various
a-aryl nitriles have been prepared in excellent yield from the corresponding a-aryl alcohols
Received 29 January 2009
Received in revised form 23 March 2009
Accepted 24 March 2009
Available online 1 April 2009
employing 3 mol % of B(C6F5)3 (1) as Lewis acid catalyst and (CH3)3SiCN (TMSCN) as cyanide source.
Cyano transfer from TMSCN to alcohol proceeds within short reaction time at rt.
produce corresponding nitriles in good to excellent yield at reflux condition.
a-Aryl thiols also
Ó 2009 Elsevier Ltd. All rights reserved.
Keywords:
Direct cyanation
a
a
-Aryl alcohols
-Aryl thiols
Lewis acid
1. Introduction
performed through prior conversion of hydroxyl group to halides and
sulfonates. However, there are only a few reports on the direct cyana-
tion of alcohols into nitriles in one-pot procedure.21 Reagent system
composed of TMSCN and InBr3 in CH2Cl2 was reported as a convenient
and efficient system for cyanation of secondary alcohols.22
Nitriles are valuable intermediates that can be transformed to
a variety of biologically important substances such as oxazoles,1 thi-
azoles,2 triazoles,3 oxadiazoles,4 and tetrazoles.5
a-Arylnitriles are
potentially valuable precursors for the synthesis of well known drugs
such as verapamil,6 indoprofen,7 cicloprofen, and naproxen.8 Direct
substitutions of the hydroxyl group in alcohols by various nucleo-
philes such as allyl-, alkynyl-, and propargylsilanes,9 1,3-dicarbonyl
compounds,10 amides11 or amines,12 and so on13 using the Lewis acid
catalysts have aroused much research interest. In these reactions, the
hydroxyl groups in alcohols can be directly substituted by the desired
nucleophiles without the need for prior transformation into the
groups that have good leaving potentials. Aryl nitriles are usually
synthesized from aryl halides using stoichiometric amount of cop-
per(I) cyanide, which has been known for over 80 years.14 Nitriles
are also prepared by dehydration of amides and aldoximes,15 acylations
of silyl ketene imines,16 hydrocyanation of olefins,17 and displacement
of aryl triflates.18 Microwave-assisted preparation of aryl nitriles has
been reported too.19 Recently palladium catalyzed cyanation of aryl
and heteroaryl chlorides has appeared in the literature.20
While various Lewis acids are employed in modern organic
synthesis, boron based reagents still remain prominent as a result
of their high Lewis acid strength and ready availability. The strong
organometallic Lewis acid, B(C6F5)3 1, has emerged in recent years
as a viable alternative to BF3.23 Owing to its uniqueness and com-
mercial availability, its applications in organic synthesis are grow-
ing and have been reviewed.24
The first commercial application of 1 was introduced as the
cocatalyst in metallocene mediated olefin polymerization.25 The
functional group transformation by 1 was initially undertaken by
Ishihara et al. for aldol type reaction.26 Recently, the applications of
1 are found in hydrosilation of alcohols,27a enones,27b carbonyl
27d
groups,27c and imines,
stereoselective transformation of epox-
ides,27e tritylation of alcohols,27f allylstannation of aromatic ale-
hydes,27g allylation of secondary benzyl acetates,27h Ferrier
azaglycosylation with sulfonamides and carbamate,27i reduction of
carbonyl group to methylene,27j cleavage of aryl and alkyl ether
with hydrosilanes,27k,l aziridines’ ring opening,27m and hydroge-
nation of imines.27n
The conversion of an alcohol into the corresponding nitrile is a fun-
damental synthetic process for carbon chain elongation. It is usually
2. Results and discussion
* Corresponding author. Tel.: þ82 32 860 7678; fax: þ82 32 867 5604.
E-mail address: sungsoo@inha.ac.kr (S.S. Kim).
Present address: Dept. of Chemistry, Govt. Arts College (Men), Nandanam,
y
We have developed several catalytic methods for the oxidation
of alcohols28 and cyanosilylation of carbonyl compounds.29 Herein
Chennai 600 035, India.
0040-4020/$ – see front matter Ó 2009 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tet.2009.03.073

4352
G. Rajagopal, S.S. Kim / Tetrahedron 65 (2009) 4351–4355
Table 2
we report 1 as a simple and effective catalyst for the direct cyan-
ation of -aryl alcohols with TMSCN at rt. This can be the first ex-
B(C6F5)3-catalyzed direct cyanation of a
-aryl alcohols with TMSCN at rta
a
ample of borane catalyzed cyanation of alcohols.
To obtain the optimized reaction conditions, we have chosen the
reaction of 4-methoxy-a-methylbenzyl alcohol with TMSCN in the
Entry
Substrate
Time (min)
Product
CN
Yieldb
90
OH
presence of B(C6F5)3 as Lewis acid catalyst. First we examined
the solvent suitability for this reaction. The data in Table 1 indicate
that CH3CN is the most appropriate solvent (entries 1–9). CH2Cl2
also acts as a good solvent for this system with little longer reaction
time (entry 7). The solvent-free reaction gave only good yield of the
corresponding nitrile (entry 10). To determine the effect of catalytic
loading for improving the yield, we have performed the reaction
with 1–20 mol % of B(C6F5)3 in CH3CN. We have found that the
reaction proceeds to give 94% yield with 3 mol % of the catalyst
(entry 4). TMSCN and n-Bu4NCN were also tested for the cyanation
reaction as cyanide source. In terms of yield and reaction time,
TMSCN gave the best results (entry 4). We have therefore chosen
entry 4 (Table 1) as the optimum reaction condition for cyanation of
1
60
(1a)
(1b)
OH
CN
2
3
60
55
90
94
(2a)
(2b)
CN
OH
MeO
Br
MeO
Br
(3a)
(3b)
(4b)
(5b)
a
-aryl alcohols.
OH
CN
Having established the standard conditions, the scope of this
protocol was examined for various
Phenylethanol (entry 1) and its para-substituted derivatives (en-
tries 2–6) are efficiently converted to corresponding -aryl nitriles
a-aryl alcohols (Table 2). sec-1-
4
5
70
60
90
89
a
(4a)
in relatively short reaction time. It is worthwhile to note that the
recently reported InBr3 catalyzed protocol22 is not amenable to sec-
1-phenylethanol for cyanation reaction. Our system, however, gives
OH
CN
excellent yield for the same substrate. ortho-Di substituted a-aryl
Cl
Cl
alcohol underwent smooth cyanation and gave moderate yield
(entry 7). The change of phenyl to naphthyl group (entries 8 and 9)
hardly influences the reactivity and also the yield. Benzhydrol un-
derwent smooth cyanation and gave an excellent yield (entry 10).
The reactions of benzhydrols having chlorine and fluorine atoms at
(5a)
Cl OH
Cl CN
6
70
85
para-position gave the corresponding a-aryl nitriles in high yields
Cl
Cl
(entries 11 and 12). Furthermore, sterically hindered triphenylme-
thanol, which is known to be a difficult substrate for cyanation
reaction, gave excellent yield in short reaction time (entry 13).
This may indicate that steric hindrance is no longer important
for the cyanation. It should be noted that alcohol having additional
methylene group in the side chain was also proved as good
substrate for cyanation reaction (entry 14). Good yields
were obtained for ortho-methoxy substituted 1-phenylpropanaol
(6a)
(6b)
OH
CN
7
8
9
60
60
60
92
90
92
(7a)
(7b)
OH
CN
(8b)
(8a)
Table 1
Direct cyanation of 4-methoxy-
a
-methylbenzyl alcohol under various reaction
CN
OH
conditionsa
OH
CN
MeO
MeO
1
+
(CH3)3SiCN
(9a)
(9b)
rt
MeO
MeO
CN
OH
Entry
Catalyst loading
(mol %)
Solvent
Time (min)
Yieldb
10
11
60
60
93
91
1
2
3
4
5
6
7
8
20
10
5
3
2
1
3
3
3
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH2Cl2
CH3Cl
30
30
60
55
90
180
70
180
240
120
120
96
96
95
94
95
90
93
40
50
75
50c
(10a)
(10b)
OH
CN
Cl
Cl
Cl
Cl
(11a)
(11b)
9
10
11
THF
No solvent
CH3CN
3
3
OH
CN
a
Reagent and condition: 1.0 mmol of 4-methoxy-a-methylbenzyl alcohol,
12
60
90
1.0 mmol of TMSCN.
F
F
F
F
b
Isolated yield.
c
(12b)
(12a)
n-Bu4NCN (5.0 mmol) was used as cyanide source.

G. Rajagopal, S.S. Kim / Tetrahedron 65 (2009) 4351–4355
4353
Table 3
Table 2 (continued )
B(C6F5)3-catalyzed direct cyanation of
temperaturea
a
-aryl thiols with TMSCN at rt and reflux
Entry
Substrate
Time (min)
Product
Yieldb
Entry
1
Substrate
Time (min) Catalyst loading
(mol %)
Product
Yieldb
OH
CN
SH
CN
13
70
93
60
3
40c
72d
120
10
(13b)
(13a)
60
120
3
10
30c
65d
SH
CN
OH
CN
2
14
15
60
70
85
80
(14b)
(14a)
OH
a
Reagent and condition: 1.0 mmol of thiol, 1.0 mmol of TMSCN.
Isolated yield.
Reaction at rt.
Reaction at reflux condition.
b
c
CN
d
OMe
(15a)
OMe
(15b)
Me
C6F5
Me
N
C
CN
OH
B
Si
C6F5
C6F5
Si CN
Me
Me
B(C6F5)3
CN
Me
Me
I
16
17
18
60
120
120
80
60
55
OH
R'
(16a)
OH
(16b)
R
CN
R
R'
III
O
O
Si(OH)(Me)3
(17a)
(17b)
B(C6F5)3
OH
CN
Me
H
+
Si
Me
O
R
R'
NC B(C6F5)3
CN-
Me
R
R'
II
(18a)
(18b)
OH
CN
N
N
19
20
140
180
40
Scheme 1. Proposed reaction pathway.
(19a)
(19b)
3. Conclusion
OH
CN
Trace
In summary, we have developed a very simple, efficient one-
step method for the synthesis -aryl nitriles from corresponding
-aryl alcohols. The significant features of this method include
(20a)
(20b)
a
a
OH
CN
operational simplicity, low catalytic loading, moisture tolerant or-
ganometallic Lewis acid catalyst, and no need of any additives. Mild
reaction condition, high yields of the products, and ease in handling
of reagents make this method more convenient for direct cyanation
21
180
Trace
(21a)
(21b)
a-aryl alcohol (1.00 mmol), TMSCN (1 mmol), 3 mol % of
a
Reagent and condition:
of a-aryl alcohol into a-aryl nitriles.
B(C6F5)3.
b
Isolated yield.
4. Experimental section
4.1. General
and
a
-cyclobenzyl alcohol (entries 15 and 16). Poor yields were
-aryl alcohols (entries 17–
obtained for heterocyclic and aliphatic
a
4.1.1. Instrumentation
19). Cyanation products were not obtained for benzyl alcohol and
cinnamyl alcohol under the present reaction conditions. The pres-
ent system requires only 3 mol % of catalyst. It is worthwhile to note
that the present protocol for cyanation reaction proceed efficiently
at rt without any additives.
We also examined commerciallyavailable secondaryand tertiary
thiols for direct cyanation reaction. The results are summarized in
Table 3. Thiols gave poor yields under optimized condition used for
the alcohols. But increase of catalytic loading and temperature gives
a good to moderate yields for the thiols (entries 1 and 2).
B(C6F5)3-catalyzed cyanosilylation reaction may follow the cat-
alytic pathway as shown in Scheme 1. Abstraction of cyanide anion
from the silane by 1 in the presence of the alcohol substrate can
lead to the formation of silyloxonium/cyanoborate ion pair (II),
which may collapse to the product.
In all the cases the 1H NMR spectra were recorded with Varian
Gemini 200 or 400 MHz instrument. Chemical shifts are reported in
parts per million in CDCl3 with tetramethylsilane as the internal
standard. 13C NMR data were collected on Varian Gemini 200 or
400 MHz instrument (50 or 100 MHz). Compounds are identified
by HRMS (EI) with Jeol DMX 303. Infrared (IR) spectra were
obtained by 370 FT-IR spectrometer.
4.2. Experimental procedure
4.2.1. General procedure for cyanation of a-aryl alcohols/thiols
To a stirred solution of alcohol/thiol (1 mmol) and B(C6F5)3
(3 mol %) in CH3CN (1 ml) TMSCN (1 mmol) was added dropwise.
The resulting solution was stirred continuously at rt for the time

4354
G. Rajagopal, S.S. Kim / Tetrahedron 65 (2009) 4351–4355
indicated in Table 2/Table 3. The reaction mixture was purified by
silica gel flash chromatography by using EtOAc–hexanes (1:9)
mixture as the eluent.
(CDCl3) d 136.3, 129.3, 128.4, 128.1, 120.2, 42.6; IR (n .
C^N) 2230 cmꢀ1
HRMS m/z calcd for C14H11N [MþH]þ 193.0891, found 193.0891.
4.2.2.11. 2,2-Bis(4-chlorophenyl)acetonitrile (11b). Yellow solid; mp
90–91 ꢁC; 1H NMR (CDCl3) 7.15–7.34 (m, 8H), 5.29 (s,1H); 13C NMR
4.2.2. Characterization data
d
(CDCl3) d 139.7,133.7,129.8,129.1,121.3, 43.9; IR (n .
C^N) 2235 cmꢀ1
4.2.2.1. 2-Phenylpropanenitrile (1b). Colorless oil; 1H NMR (CDCl3)
HRMS m/z calcd for C14H9Cl2N [MþH]þ 261.0112, found 261.0090.
d
7.32–7.40 (m, 5H), 3.91 (q, J¼10.81 Hz, H), 1.64 (d, J¼3.7 Hz, 3H);
13C NMR (CDCl3)
d
136.9, 129.0, 127.9, 126.6, 121.5, 31.1, 21.36; IR
4.2.2.12. 2,2-Bis(4-fluorophenyl)acetonitrile (12b). Colorless oil; 1H
(n
C^N) 2237 cmꢀ1. HRMS m/z calcd for C9H9N [MþH]þ 131.0735,
NMR (CDCl3,)
NMR (CDCl3)
d C
7.48–7.55 (m, 4H), 7.21–7.34(m, 4H), 5.56 (s,1H); 13
found 131.0731.
d 161.4, 135.4, 132.7, 121.8, 117.8, 44.1; IR (nC^N)
2239 cmꢀ1. HRMS m/z calcd for C14H9F2N [MþH]þ 229.0703, found
4.2.2.2. 2-p-Tolylpropanenitrile (2b). Colorless oil; 1H NMR (CDCl3)
229.0703.
d
7.10–7.23 (m, 4H), 4.19 (q, J¼7.3 Hz, H), 2.34 (s, 3H), 1.34 (d,
J¼7.3 Hz, 3H); 13C NMR (CDCl3)
d
137.2, 135.9, 129.1, 126.2, 121.2,
4.2.2.13. 2,2,2-Triphenylacetonitrile (13b). White solid; mp 129–
30.9, 21.2, 20.6; IR (
n
C^N) 2220 cmꢀ1. HRMS m/z calcd for C10H11
N
130; 1H NMR (CDCl3)
d
7.21–7.41 (m, 15H); 13C NMR (CDCl3)
d
140.1,
[MþH]þ 145.0891, found 145.0893.
128.8, 128.6, 128.1, 123.4, 57.3; IR (n
C^N) 2240 cmꢀ1. HRMS m/z
calcd for C20H15N [MþH]þ 269.1204, found 269.1200.
4.2.2.3. 2-(4-Methoxyphenyl)propanenitrile (3b). Colorless oil; 1H
NMR (CDCl3)
d
7.60 (d, J¼8.0 Hz, 2H), 7.23 (d, J¼8.0 Hz, 2H), 4.18 (q,
4.2.2.14. 2-Phenylbutanenitrile (14b). Colorless oil; 1H NMR
J¼4.7 Hz, 1H), 4.14 (s, 3H), 1.94 (d, J¼4.7 Hz, 3H); 13C NMR (CDCl3)
(CDCl3,)
d
7.33–7.41 (m, 5H), 3.77 (t, J¼7.2 Hz, 1H), 1.93–2.00 (m,
d
159.2, 129.1, 127.8, 121.9, 114.4, 55.3, 36.4, 21.36; IR (
n
C^N)
2H), 1.10 (t, J¼7.3 Hz, 3H); 13C NMR (CDCl3)
d 135.7, 129.0, 128.0,
2233 cmꢀ1. HRMS m/z calcd for C10H11NO [MþH]þ 161.0841, found
127.3, 120.8, 38.84, 29.2, 11.4. HRMS m/z calcd for C10H11N [MþH]þ
161.0844.
145.0891, found 145.0889.
4.2.2.4. 2-(4-Bromophenyl) propanenitrile (4b). Colorless oil; 1H
4.2.2.15. 2-(2-Methoxyphenyl)butanenitrile (15b). Colorless oil; 1H
NMR (CDCl3)
d
7.43 (d, J¼7.8 Hz, 2H), 7.14 (d, J¼7.8 Hz, 2H), 4.16 (q,
NMR (CDCl3,)
d
6.60–7.20 (m, 4H), 4.10 (t, J¼7.0 Hz, 1H), 3.72 (s, 3H),
J¼4.9 Hz, 1H), 1.34 (d, J¼5.7 Hz, 3H); 13C NMR (CDCl3)
d
142.8, 131.6,
1.79–1.94 (m, 2H), 0.75–0.85 (m, 3H); 13C NMR (CDCl3)
d
158.0,
131.3, 127.9, 127.8, 121.2, 24.5; IR (
n
C^N) 2230 cmꢀ1. HRMS m/z
133.1,129.2,126.4,123.2,120.4,114.3, 56.3, 29.3, 27.1,11.6; HRMS m/z
calcd for C11H13NO [MþH]þ 175.0997, found 175.0989.
calcd for C9H8BrN [MþH]þ 208.9840, found 208.9844.
4.2.2.5. 2-(4-Chlorophenyl) propanenitrile (5b). Colorless oil; 1H
4.2.2.16. 2-Cyclopropyl-2-phenylacetonitrile (16b). Colorless oil; 1H
NMR (CDCl3)
d
7.28 (d, J¼7.4 Hz, 2H), 6.98 (d, J¼7.4 Hz, 2H), 4.11 (q,
NMR (CDCl3)
d
6.05–7.29 (m, 5H), 3.38 (d, J¼7.2 Hz, 1H), 0.41–0.46
J¼4.7 Hz, 1H), 1.31 (d, J¼5.6 Hz, 3H); 13C NMR (CDCl3)
d
140.6, 130.3,
(m, 4H), 0.59–0.64 (m, 1H); 13C NMR (CDCl3)
d 138.8, 129.0, 128.3,
131.1, 125.8, 125.3, 120.6, 24.1; HRMS m/z calcd for C9H8ClN [MþH]þ
127.3, 120.1, 39.1, 12.5, 4.2; HRMS m/z calcd for C11H11N [MþH]þ
165.0345, found 165.0341.
157.0891, found 157.0898.
4.2.2.6. 2-(2,6-Dichlorophenyl)-propionitrile (6b). Colorless oil; 1H
4.2.2.17. 2-Furan-2-yl-propionitrile (17b). Colorless oil; 1H NMR
NMR (CDCl3)
d
6.90–7.11 (m, 3H), 4.43 (q, J¼5.7 Hz, 1H), 1.30 (d,
(CDCl3,)
d
6.05–7.29 (m, 3H), 4.38 (q, J¼7.2 Hz, 1H), 1.80(d, J¼7.2 Hz,
J¼5.6 Hz, 3H); 13C NMR (CDCl3)
d
138.6, 127.8, 127.1, 124.1, 115.3,
3H); 13C NMR (CDCl3)
d 153.8, 139.0, 115.41, 109.8, 103.6, 30.6, 11.3;
44.2, 25.3; HRMS m/z calcd for C9H7Cl2N [MþH]þ 198.9956, found
HRMS m/z calcd for C7H7NO [MþH]þ 121.0528, found 121.0532.
165.9951.
4.2.2.18. 2-Methyl-but-3-ynenitrile (18b). Colorless oil; 1H NMR
(CDCl3,)
4.2.2.7. 3,3-Dimethyl-2-phenylbutanenitrile (7b). Colorless oil; 1H
d
4.1 (q, J¼7.2 Hz, 1H), 2.17 (s, 1H), 1.82(d, J¼7.2 Hz, 3H); 13
C
NMR (CDCl3)
(CDCl3)
d
7.28–7.29 (m, 5H), 4.29 (s, 1H), 0.89 (9H, s); 13C NMR
NMR (CDCl3) d 118.4, 85.3, 65.2, 24.5, 13.5; HRMS m/z calcd for
d
135.8, 131.9,131.0,129.6, 126.3, 121.3, 36.0, 27.3; IR (
n
C^N)
C5H5N [MþH]þ 79.0422, found 79.0426.
2227 cmꢀ1. HRMS m/z calcd for C12H15N [MþH]þ 173.1204, found
173.1208.
4.2.2.19. 3-Dimethylamino-2-methyl-propionitrile (19b). Colorless
oil; 1H NMR (CDCl3,)
d
3.7 (q, J¼7.1 Hz,1H), 2.85–3.05 (m, 2H), 2.07 (s,
4.2.2.8. 2-(Naphthalen-2-yl)propanenitrile (8b). Colorless oil; 1H
6H), 1.52 (d, J¼6.8 Hz, 3H); 13C NMR (CDCl3)
d 120.4, 55.3, 39.2, 25.5,
NMR (CDCl3)
d
7.82–7.90 (m, 3H), 7.67 (s, 1H), 7.49–7.53 (m, 3H),
15.5. HRMS m/z calcd for C6H12N2 [MþH]þ 112.1000, found 112.1006.
4.47 (q, J¼7.1 Hz, 1H), 1.50 (d, J¼7.1 Hz, 3H); 13C NMR (CDCl3)
d
138.4, 135.6, 133.2, 131.1, 129.3, 128.9, 127.6, 126.8, 125.6, 125.1,
Acknowledgements
121.5, 31.3, 21.8; IR (n N
C^N) 2220 cmꢀ1. HRMS m/z calcd for C15H11
[MþH]þ 205.0891, found 205.0897.
This work has been supported by Inha University Research Grant
2009. One of us (G.R.) thanks The Secretary (Higher Education,
Tamil Nadu, India) and Director (Directorate of Collegiate Educa-
tion, Tamil Nadu, India) for permitting him to carry out the post-
doctoral research in Korea.
4.2.2.9. 2-(6-Methoxynaphthalen-2-yl)propanenitrile (9b). Pale yellow
solid; mp 72–73 ꢁC; 1H NMR (CDCl3)
7.75 (t, J¼8.0 Hz, 3H), 7.33–
d
7.41 (m, 1H), 7.12–7.26 (m, 2H), 4.07 (q, J¼7.1 Hz, 1H), 3.92 (s, 3H),
1.71 (d, J¼7.1 Hz, 3H); 13C NMR (CDCl3)
d 157.9, 133.9, 131.9, 129.2,
128.6, 127.8, 125.2, 124.8, 121.7, 119.4, 105.5, 55.2, 31.0, 21.3; IR
(n
C^N) 2227 cmꢀ1
.
HRMS m/z calcd for C16H13NO [MþH]þ
References and notes
235.0997, found 235.0996.
1. Connell, R.; Scavo, F.; Helquist, P.; Akermark, B. Tetrahedron Lett. 1986, 27, 5559–
5562.
2. Kerdesky, F. A. J.; Holms, J. H.; Moore, J. L.; Bell, R. L.; Dyer, R. D.; Carter, G. W.;
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4.2.2.10. 2,2-Diphenylacetonitrile (10b). Pale yellow solid; mp 73–
74 ꢁC; 1H NMR (CDCl3)
d
6.99–7.14 (m, 10H), 5.15 (s, 1H); 13C NMR

G. Rajagopal, S.S. Kim / Tetrahedron 65 (2009) 4351–4355
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