2-Chloro-8,8-dimethyl-8,9-dihydro-7H-chromeno[2,3-b]quinoline-10,12-dione

Abstract

The asymmetric unit of the title compound, C18H14ClNO3, contains two independent molecules (A and B). In both molecules, the cyclohexanone ring has a chair conformation. The dihedral angles between the pyran ring and the pyridine and chlorophenyl rings are 2.13 (9) and 2.19 (9)°, respectively, in A, and 0.82 (9) and 1.93 (9)°, respectively, in B. The carbonyl O atoms deviate from the pyran and benzene rings to which they are attached by −0.092 (2) and 0.064 (2) Å, respectively, in A, and by −0.080 (2) and −0.063 (2) Å, respectively, in B. In the crystal, the A molecules are linked via C—H...O hydrogen bonds, forming double-stranded chains along [100]. They lie parallel to the double-stranded chains formed by the B molecules, which are also linked via C—H...O hydrogen bonds. The chains stack up the c axis in an –A–A–B–B–A–A– manner, with a number of π–π interactions involving A and B molecules; the centroid–centroid distances vary from 3.4862 (11) to 3.6848 (11) Å