New Journal of Chemistry
Page 4 of 5
DOI: 10.1039/C7NJ03405A
2
(a) Z. Rappoport, Chemistry of the Cyano Group, Wiley, London,
1970; (b) R. C. Larock, Comprehensive Organic Transformations:
A Guide to Functional Group Preparations, VCH, New York, 1989.
T. Sandmeyer, Ber. Dtsch. Chem. Ges., 1884, 17, 1633.
K.W. Rosenmund and E. Struck, Ber. Dtsch. Chem. Ges., 1919, 2,
1749.
at the vinylic CꢀBr bond to give 4b as the major product in a
yield of 56%. A triphenyl substituted vinyl bromide was also
reactive with 2a, affording a highly conjugated acylonitrile 4c
in a sastisfying yield of 74%. Finally, vinyl boronic acid is
also feasible for this reaction to prepare 4d in an isolated yield
of 60%.
50
55
60
65
70
75
80
85
3
4
5
5
6
For reviews on transition metalꢀcatalyzed cyanation reactions, see:
(a) G. P. Ellis and T. M. RomneyꢀAlexander, Chem. Rev., 1987, 87,
779; (b) J. Kim, H. J. Kim and S. Chang, Angew. Chem., Int. Ed.,
2012, 51, 11948; (c) P. Anbarasan, T. Schareina and M. Beller,
Chem. Soc. Rev., 2011, 40, 5049; (d) Q. Wen, J. Jin, L. Zhang, Y.
Luo, P. Lu and Y. Wang, Tetrahedron Lett., 2014, 55, 1271.
Aryl halides with cyanides: (a) J. Zanon, A. Klapars and S. L.
Buchwald, J. Am. Chem. Soc., 2003, 125, 2890; (b) H.ꢀJ. Cristau, A.
Ouali, J.ꢀF. Spindler and M. Taillefer, Chem.–Eur. J., 2005, 11,
2483; (c) T. Schareina, A. Zapf and M. Beller, Tetrahedron Lett.,
2005, 46, 2585; (d) T. Schareina, A. Zapf, W. Magerlein, N. Müller
and M. Beller, Chem.–Eur. J., 2007, 13, 6249; (e) D. Wang, L.
Kuang, Z. Li and K. Ding, Synlett, 2008, 69; (f) P. Y. Yeung, C. M.
So, C. P. Lau and F. Y. Kwong, Org. Lett., 2011, 13, 648; (g) P. Y.
Yeung, C. M. So, C. P. Lau and F. Y. Kwong, Angew. Chem., Int.
Ed., 2010, 49, 8918; (h) P. Y. Yeung, C. P. Tsang and F. Y. Kwong,
Tetrahedron Lett., 2011, 52, 7038.
For Cuꢀmediated cyanation of aryl boronic acids: see: (a) G. Zhang,
L. Zhang, M. Hu and J. Cheng, Adv. Synth. Catal., 2011, 353, 291;
(b) C. W. Liskey, X. Liao and J. F. Hartwig, J. Am. Chem. Soc.,
2010, 132, 11389; (c) G. Zhang, S. Chen, H. Fei, J. Cheng and F.
Chen, Synlett, 2012, 2247; (d) Y. Luo, Q. Wen, Z. Wu, J. Jin, P. Lu
and Y. Wang, Tetrahedron, 2013, 69, 8400; (e) Z. Zhang and L. S.
Liebeskind, Org. Lett., 2006, 8, 4331. For more examples of Pdꢀ
mediated cyanation of boronic acids, see: ref 5c.
O
NC
R
O
Ar LG
LG
Ar CN
CN
+
O2
LnCuΙ
X
LnCu CN
B
A
(i) transmetalation
(ii) cyanation
(LG = Halo, B(OH)2)
Scheme 2 Proposed mechanism for this cyanation reaction.
Radical trapping experiment showed that 3a was obtained
10 in only 10% yield in the presence of 2 equivalents of radical
scavenger TEMPO (2,2,6,6ꢀtetramethylpiperidinyloxy) (68%
without TEMPO), suggesting the involvement of radical
species during the reaction course.19 Based on this finding and
insights gained from closely related reactions,17b a plausible
15 mechanism is suggested to comprise two stages:
transmetalation and cyanation. A key LnCuꢀCN intermediate
B may be formed by transmetalation of CN group from αꢀ
cyanoacetate via oxidative CꢀCN bond cleavage17,20 promoted
by TBHP/O2 during which radical species are possibly
20 involved. A rateꢀlimiting reaction of B with aryl/vinyl boronic
acid or halide would install the cyano group on the aromatic
or vinylic Cipso position.
In summary, a protocol for aromatic and vinylic cyanation
is described to prepare aryl nitriles and acrylonitriles using
25 readily available and nontoxic αꢀcyanoacetates as the
cyanating reagents. This reaction is mediated by CuI/PPh3 in
the presence of TBHP/HOAc under oxygen, and is compatible
with aryl/vinyl boronic acids and halides. The reaction is
potentially attractive for practical synthesis of various aryl
30 nitriles and acrylonitriles.
7
8
9
For cyanation of vinyl halides, see: (a) A. Pradal and G. Evano,
Chem. Commun., 2014, 50, 11907; (b) K. J. Powell, L.ꢀC. Han, P.
Sharma and J. E. Moses, Org. Lett., 2014, 16, 2158; (c) M. Shevlin,
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Mukherjee and B. C. Ranu, Org. Biomol. Chem., 2012, 10, 952.
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Chem., Int. Ed., 2003, 42, 1661; (b) T. Schareina, A. Zapf, A. Cott,
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Park, S. Lee and S. Chang, J. Org. Chem., 2010, 75, 2760.
90 10 CH3CN: (a) F.ꢀH. Luo, C.ꢀI. Chu and C.ꢀH. Cheng, Organometallics
1998, 17, 1025; (b) Y. Zhu, L. Li and Z. Shen, Chem.–Eur. J.,
2015, 21, 13246.
11 Benzyl nitrile: a) Q. Wen, J. Jin, B. Hu, P. Lu, Y. Wang, RSC Adv.,
2012, 2, 6167; b) J. Jin, Q. Wen, P. Lu, Y. Wang, Chem. Commun.,
2012, 48, 9933; c) O. Y. Yuen, P. Y. Choy, W. K. Chow, W. T.
Wong and F. Y. Kwong, J. Org. Chem., 2013, 78, 3374.
12 DMF: S. Ding and N. Jiao, J. Am. Chem. Soc., 2011, 133, 12374.
13 CH3NO2: X. Chen, X.ꢀS. Hao, C. E. Goodhue and J.ꢀQ. Yu, J. Am.
Chem. Soc., 2006, 128, 6790.
100 14 J. Kim and S. Chang, J. Am. Chem. Soc., 2010, 132, 10272.
15 (a) J. Kim, J. Choi, K. Shin and S. Chang, J. Am. Chem. Soc., 2012,
134, 2528; (b) K. V. V. K. Mohan, N. Narender and S. J. Kulkarni,
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Org. Lett., 2012, 14, 3924; (d) X. Ren, J. Chen, F. Chen and J.
Conflicts of interest
95
There are no conflicts of interest to declare.
Acknowledgements
This study was supported by the National Natural Science
35 Foundation of China (No. 21472068).
Notes and references
105
110
115
Cheng, Chem. Commun., 2011, 47, 6725; (e) G. Zhang, X. Ren, J.
Chen, M. Hu and J. Cheng, Org. Lett., 2011, 13, 5004.
16 Z. Wang and S. Chang, Org. Lett., 2013, 15, 1990.
17 (a) S.ꢀL. Zhang and L. Huang, Org. Biomol. Chem., 2015, 13, 9963.
(b) S.ꢀL. Zhang and X.ꢀJ. Wang, Org. Lett., 2017, 19, 3139; (c) S.ꢀ
L. Zhang, L. Huang and W.ꢀF. Bie, Organometallics, 2014, 33,
3030.
18 For a pioneering study using αꢀcyanoacetates, see: (a) S. Zheng, C.
Yu and Z. Shen, Org. Lett., 2012, 14, 3644. For a related study
leading to different products, see: (b) P. Y. Yeung, K. H. Chung and
F. Y. Kwong, Org. Lett., 2011, 13, 2912.
a
Key Laboratory of Synthetic and Biological Colloids, Ministry of
Education, School of Chemical and Material Engineering, Jiangnan
University, Wuxi 214122, Jiangsu Province, China. Fax/Tel.: +86-510-
40 85917763; E-mail: slzhang@jiangnan.edu.cn
† Electronic Supplementary Information (ESI) available: Experimental
1
details, characterization data, copies of H and 13C NMR spectra for all
the products. See DOI: 10.1039/b000000x/
1
(a) A. Kleemann, J. Engel, B. Kutscher and D. Reichert,
Pharmaceutical Substance: Synthesis Patents, Applications, 4th ed.,
Georg Thieme, Stuttgart, 2001; (b) J. S. Miller and J. L. Manson,
Acc. Chem. Res., 2001, 34, 563; (c) F. F. Fleming and Q. Wang,
Chem. Rev., 2003, 103, 2035.
45
19 Efforts to determine the fate of TEMPO were unsuccessful.
20 For a review on C−CN bond cleavage, see: M. Tobisu and N.
Chatani, Chem. Soc. Rev., 2008, 37, 300.
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