Collection of Czechoslovak Chemical Communications - digital archive 

Abstract

Three-dimensional crystal structures of a diphenyl sulfide skeleton from various compounds were confronted with computed conformational map. Diphenyl sulfide fragments, 31 in total, were retrieved from the Cambridge Structural Database and four fragments were taken from our measurements. Due to the symmetry of the fragment, the number of analyzed fragments rose to 140. The main features of geometrical behaviour of the fragment can be summarized as follows: If an endocyclic torsion angle of a phenyl ring deviates from 0 °C, the adjacent torsion angle is deformed in opposite direction by the same value keeping thus the phenyl ring planar. Repulsion of phenyl rings enlarges a C-S-C bonding angle in all fragments and bends aside the phenyl ring from a symmetrical attachment which has torsion around a S-C bond near 0°. Torsion angles around the S-C bonds correlate with each other keeping approximately perpendicular orientation of the phenyl rings. The correspondence between experimental values of torsion angles and low energy regions of the molecular mechanics conformational map suggests that possible gas-phase and crystal conformations of the diphenyl sulfide molecule are the same. Ab initio calculations fully confirmed results of molecular mechanics and - along with the crystal conformations - justify further usage of molecular mechanics in computational modelling of diphenyl sulfides.