Crystal structure of ethyl 2-amino-4-(4-chloro-phen-yl)-4H-1-benzothieno[3,2-b]pyran-3-carboxyl-ate.

The title compound, C20H16ClNO3S, is built up from three fused rings, one five- and two six-membered rings, linked to a 3-eth­oxy­carbonyl group and to a 4-chloro­phenyl ring. The hydropyran ring has a flattened envelope conformation, with the C atom substituted by the 4-chloro­phenyl ring as the flap (displaced by 0.077 (2) A from the plane through the other atoms). The fused three-ring system is quasi-planar (r.m.s. deviation = 0.057 A), with the largest deviation from the mean plane being 0.106 (1) A for the C atom substituted by the 4-chloro­phenyl ring. The 4-chloro­phenyl 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 intra­molecular N—H⋯O hydrogen bond forming an S(6) ring motif. In the crystal, mol­ecules are linked by pairs of N—H⋯O hydrogen bonds, forming inversion dimers with an R22(12) ring motif. There are also short inter­molecular Cl⋯O inter­actions present [3.1226 (12) A] between neighbouring mol­ecules.