9-(4-Formylphenyl)-3,3,6,6-tetramethyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione

Abstract

In the title compound, C24H26O4, the central 4H-pyran ring adopts a flattened boat conformation, with the mean and maximum deviations of the ring being 0.0582 (6) and 0.1012 (3) Å, respectively. The two cyclohexenone rings on opposite sides of the pyran ring each adopt an envelope conformation; the C atom bearing a dimethyl substituent is the flap atom in each case. The mean planes of the pyran ring and the substituent benzene ring subtend a dihedral angle of 86.45 (2)°. In the crystal, molecules are linked into inversion dimers via pairs of C—H...O hydrogen bonds.

Keywords

• crystal structure
• dimedone
• xanthenedione
• terephaldehyde