Crystal structure of ethyl 2-amino-4-(4-chloro­phen­yl)-4H-1-benzothieno[3,2-b]pyran-3-carboxyl­ate

The title compound, C20H16ClNO3S, is built up from three fused rings, one five- and two six-membered rings, linked to a 3-eth-oxy-carbonyl group and to a 4-chloro-phenyl ring. The hydropyran ring has a flattened envelope conformation, with the C atom substituted by the 4-chloro-phenyl ring as the flap (displaced by 0.077 (2) Å from the plane through the other atoms). The fused three-ring system is quasi-planar (r.m.s. deviation = 0.057 Å), with the largest deviation from the mean plane being 0.106 (1) Å for the C atom substituted by the 4-chloro-phenyl ring. The 4-chloro-phenyl ring is approximately perpendicular to the mean plane of the fused ring system, as indicated by the dihedral angle of 77.32 (6)° between their mean planes. There is an intra-molecular N-H⋯O hydrogen bond forming an S(6) ring motif. In the crystal, mol-ecules are linked by pairs of N-H⋯O hydrogen bonds, forming inversion dimers with an R 2 (2)(12) ring motif. There are also short inter-molecular Cl⋯O inter-actions present [3.1226 (12) Å] between neighbouring mol-ecules.