A novel synthesis of benzo[b]thiophene
Received: 11 September 2012 / Accepted: 8 November 2012 / Published online: 9 December 2012
Ó Springer Science+Business Media Dordrecht 2012
Abstract We report a convenient method of preparation of benzo[b]thiophene,
using 2-chlorobenzaldehyde and 2-mercaptoacetonitrile as starting materials. The
process comprises two steps, neither of which has been reported previously. The
reactions in this work are clean and efﬁcient.
Keywords Benzo[b]thiophene Á Coupling Á Decyanation
Benzo[b]thiophene and its derivatives are important, because they are widely used in
the preparation of, for example, medicines [1–5], pesticides [6, 7], and semicon-
ductors [8, 9]. Benzo[b]thiophene can be synthesized by benzene ring closure or
thiophene ring closure. Kitamura et al.  reported the synthesis of benzo[b]thi-
ophene by cyclization of (2-(2-bromovinyl)phenyl)(methyl)sulfane; Rudzki et al.
 synthesized benzo[b]thiophene from ((2-bromophenyl)ethynyl)trimethylsilane
via cyclization with sodium sulﬁde; Voronkov et al.  reported the synthesis of
benzo[b]thiophene by cyclization of (1,2-dichloroethyl)benzene and hydrogen
sulﬁde; Denyagina et al.  reported cyclization of bromobenzene, ethyne, and
hydrogen sulﬁde to give benzo[b]thiophene; Reinecke et al.  reported two-step
benzene ring closure using thiophene-2,3-dicarboxylic acid as the starting material.
There are also many other methods of preparation of benzo[b]thiophene [15–19]; for
these, however, yields are much lower.
We recently found a new method of preparation of benzo[b]thiophene using
2-chlorobenzaldehyde and 2-mercaptoacetonitrile as starting materials.
Z. Liao (&) Á X. Lv Á M. Tao
Jiangxi Renming Pharmaceutical Chemicals Ltd., Jiangxi 332700, China
Res Chem Intermed (2013) 39:4021–4024