5-Amino-7-(3-chloro-phen-yl)-3,7-di-hydro-2H-thieno[3,2-b]pyran-6-carbo-nitrile 1,1-dioxide

The title compound, C14H11ClN2O3S, with fused thiophene and pyran rings, was synthesized via the condensation of dihydrothiophen-3(2H)-one 1,1-dioxide and 2-(3-chlorobenzylidene)malononitrile catalysed by triethylamine in ethanol. The thiophene ring adopts an envelope conformation and the pyran ring is planar (r.m.s. deviation = 0.0067 Å). The dihedral angle between the pyran and phenyl rings is 80.8 (1)°. The crystal packing is stabilized by intermolecular N—H...N and N—H...O hydrogen bonds in which the cyano N and sulphone O atoms, respectively, acting as acceptors.