Synthesis of 2-amino-4-phenyl-6-(phenylsulfanyl)-3,
5-dicyanopyridines by tandem reaction
Received: 4 December 2012 / Accepted: 17 December 2012 / Published online: 4 January 2013
Ó Springer Science+Business Media Dordrecht 2013
A novel basic ionic liquid, 1-(2-aminoethyl)pyridinium hydroxide, con-
taining both Brønsted base and Lewis base sites has been used as an efﬁcient catalyst
for the synthesis of 2-amino-4-phenyl-6-(phenylsulfanyl)-3,5-dicyanopyridines. The
condensation and oxidation tandem reaction of aldehydes, malononitrile, and thiols,
performed in aqueous ethanol, afforded reasonable to good yields within 30–60 min.
After the reaction, the catalyst could be recycled and reused. A possible mechanism to
account for the tandem reaction is proposed.
Keywords 2-Amino-4-phenyl-6-(phenylsulfanyl)-3,5-dicyanopyridine Á
Synthesis Á Basic ionic liquid Á Catalyst Á Tandem reaction
The pyridine ring is an important constituent of a wide range of naturally occurring
and synthetic bioactive compounds, pharmaceuticals, and functional materials .
Among these, substitution of the 6-position of the pyridine ring with thio-containing
groups furnishes a class of medicinally signiﬁcant compounds, for example
antiprion agents [2, 3], non-nucleoside agonists of the human adenosineA1 receptor
, and an inhibitor of HIV-1 integrase . Substituted pyridine derivatives are
important heterocyclic compounds, because many have biological activity as
potential antimicrobial and anti-inﬂammatory agents, acetylcholinesterase inhibi-
tors, analgesics, bactericides, and muscle relaxants [6–8].
D. Hao Á Z. Yun-lei Á S. Xiao-peng Á Y. Jin-ming Á F. Dong (&)
Department of Pharmaceutical Engineering, Yancheng Normal University, Yancheng 224002,
Jiangsu, People’s Republic of China
50 Kai Fang Da Dao, Yancheng 224002, Jiangsu, People’s Republic of China
Res Chem Intermed (2014) 40:587–594