Crystallographic and conformational analysis of 1,3-bis(2,4-dimethoxyphenyl)imidazolidine-2-thione

Abstract

The molecular and crystal structures of the title compound, C19H22N2O4S, were determined by single crystal X-ray diffraction technique. The title compound crystallizes in space group F d d 2, with a = 30.785(3) angstrom, b = 10.6455(9) angstrom, c = 11.0036(8) angstrom, Z = 8, D-calc = 1.379(2) g cm(-3), mu(Mo-K-alpha) = 0.207 mm(-1), and its crystal system is orthorhombic. The structure was solved by direct methods and refined to a final R = 0.042 for 1530 reflections with I > 2 sigma (I). There is a half-independent molecule in the asymmetric unit. The title molecule has twofold rotational symmetry along with the C-S bond. Classically no hydrogen bond is found in the crystal structure. The crystal structure is stabilized by pi-pi stacking and edge to face (C-H...pi-ring) interactions. To elucidate conformational features and steric hindrances of the title molecule, selected torsion angle is varied from -180 degrees to +180 degrees in every 10 degrees and thus molecular energy profile is calculated by PM3 semi-empirical method.