Crystal and molecular structures of diastereomeric 2-phosphoryl-, 2-thiophosphoryl-, and 2-selenophosphoryl-substituted 1,3-dithianes

The crystal and molecular structures of five pairs of diastereomeric cis- and trans-2-phosphoryl-, 2-thiophosphoryl-, and 2-selenophosphoryl-5-t-butyl-1,3-dithianes have been determined. For all the examined compounds, 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 differences in corresponding bond lengths and valence angles in diastereomeric cis- and trans-2-P-substituted 1,3-dithianes are discussed.