Ethyl 5-hydroxy-6-oxo-4-phenyl-5,6-dihydro-4H-cyclopenta[b]thiophene-5-carboxylate

Abstract

In the title molecule, C16H14O4S, the dihydrocyclopentathiophenone ring system is almost planar, with an r.m.s. deviation of 0.060 Å from the best fit plane through all nine non-H atoms. The cyclopentanone ring adopts a severely flattened envelope conformation with the C atom carrying the OH and ethylcarboxylate substituents at the flap. This atom lies only 0.185 (3) Å from the plane through the other four C atoms. The phenyl substituent is inclined at 43.37 (5)° to the dihydrocyclopentathiophenone mean plane. In the crystal, molecules are linked by pairs of O—H...O hydrogen bonds, forming inversion dimers with R22(10) ring motifs. Weak C—H...O hydrogen bonds also link molecules into chains along c, while an approximately orthogonal set of C—H...O contacts form chains along b, resulting in layers lying parallel to (100). Inversion dimers also form through weaker R22(12) C—H...S contacts, which combine with C—H...O contacts to form stacks along b.