Ethyl 2-[2-(4-oxo-4H-chromen-2-yl)phen-oxy]acetate

摘要

In the title flavonoid derivative, C 19 H 16 O 5 , the chromene portion is planar (r.m.s. deviation = 0.022??) with the substituents lying closely to the same plane. The dihedral angle between its mean plane and that of the benzene ring is 4.9?(1)°. This planarity is due, in part, to the presence of a strong intra-molecular C—H?O hydrogen bond and to two weak C—H?O contacts. In the crystal, neighboring mol-ecules are linked by a C—H?O hydrogen bond and a C—H? π inter-action, forming chains along the a -axis direction.