N'-[1-(2,4-Dioxo-3,4-dihydro-2H-1-benzopyran-3-yl-idene)eth-yl]thiophene-2-carbo-hydrazide

Abstract

The title compound, C(16)H(12)N(2)O(4)S, was obtained by the condensation of 3-acetyl-4-hy-droxy-coumarin with thien-2-ylcarbonyl hydrazide. The pyran ring adopts a 2,4-dione tautomeric form. The benzopyran ring system is almost coplanar with the thio-phene ring [dihedral angle 0.9 (2)°]. The exocyclic C=C double bond has an E geometry. The mol-ecular conformation is stabilized by an intra-molecular N-H⋯O hydrogen bond. In the crystal, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into chains along the a axis.

Fig. 1.

Reaction scheme.

Fig. 2.

The molecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level.

Fig. 3.

Partial crystal packing of the title compound showing the intra- and intermolecular hydrogen bonds, the latter linking the molecules into one-dimensional chains along the a. H atoms not involved in hydrogen bonding are omitted.