(2E,7E)-2,7-Bis[(thiophen-2-yl)methylidene]cycloheptanone

Abstract

The whole molecule of the title compound, C17H16OS2, is generated by two-fold rotational symmetry. The carbonyl C and O atoms of the cycloheptanone ring lie on the twofold rotation axis which bisects the opposite –CH2–CH2– bond of the ring. The molecule exists in an E,E conformation with respect to the C=C double bond. The cycloheptanone ring exhibits a twisted chair conformation and its mean plane makes a dihedral angle of 50.12 (19)° with the planes of the thiophene rings. The two S atoms are in an anti arrangement with respect the carbonyl O atom and the dihedral angle between the two thiophene ring planes is 69.38 (7)°. In the molecule, there are two intramolecular C—H...S hydrogen bond, forming S(6) ring motifs. In the crystal, inversion dimers are generated via pairs of C—H...O hydrogen bonds. These dimers are interconnected by another interaction of the same kind with a neighbouring molecule, forming a molecular chain along the c-axis direction.