Ethyl 7-oxo-7H-benzo[de]imidazo[5,1-a]isoquinoline-11-carboxylate–trifluoroacetic acid (1/1)

Abstract

The structure of the title trifluoroacetic acid adduct, C17H12N2O3·C2HF3O2, contains a trifluoroacetic acid molecule hydrogen bonded to the imine N atom of the imidazole ring of a nearly planar four-fused-ring system (r.m.s. deviatiation = 0.013 Å). The carboxylic acid group of the triflouroacetic acid molecule is twisted with respect to the mean plane of the four-fused-ring sytem by 75.9 (2)°. A short intramolecular C—H...O hydrogen bond occurs. In the crystal, the adduct molecules are arranged into stacks along the b axis via π–π interactions between imidazole rings and between imidazole and one of the benzene rings [centroid–centroid distances 3.352 (2) and 3.485 (2) Å, respectively]. Molecules are linked via C—H...O hydrogen bonds, forming an alternating polymeric head-to-head/tail-to-tail stepped chain approximately along the a-axis direction and tilted on an axis bisecting the b and c axes.