CRYSTAL AND MOLECULAR-STRUCTURES OF DIASTEREOMERIC 2-PHOSPHORYL-SUBSTITUTED, 2-THIOPHOSPHORYL-SUBSTITUTED, AND 2-SELENOPHOSPHORYL-SUBSTITUTED 1,3-DITHIANES

The crystal and molecular structures of five pairs of diastereomeric c is- and trans-2-phosphoryl-, 2-thiophosphoryl-, and 2-selenophosphoryl -5-t-butyl-1,3-dithianes have been determined. For all the examined co mpounds, all of the basic geometrical parameters, such as bond lengths , bond and torsion angles, and the deformation of a chair conformation of the six-membered heterocyclic rings, have been established. The di fferences in corresponding bond lengths and valence angles in diastere omeric cis- and trans-2-P-substituted 1,3-dithianes are discussed.