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

Abstract

Key indicators: single-crystal X-ray study; T = 296 K; mean (C-C) = 0.004 Å; R factor = 0.049; wR factor = 0.162; data-to-parameter ratio = 14.1.The whole molecule of the title compound, C 17 H 16 OS 2 , 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 -CH 2 -CH 2 -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-HÁ Á ÁS hydrogen bond, forming S(6) ring motifs. In the crystal, inversion dimers are generated via pairs of C-HÁ Á ÁO 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. Related literature

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