Polarity and Structure of Se-Esters of Diselenophosphinic Acids: Experimental and Theoretical Conformational Analysis in Solution

Abstract

Conformational analysis of Se-esters of diselenophosphinic acids has been performed and their polarities have been determined using the methods of dipole moments and quantum chemistry (DFT [B3PW91/6-311++G(df,p)]+CPCM). In solution, the studied compounds exist as an equilibrium of several conformers with staggered gauche and trans- or eclipsed cis-orientation of the substituents relative to the P=Se bond. The presence of eclipsed cis-conformations is explained by the formation of intramolecular H⋯Se bonds involving the hydrogen atom of the Se-alkyl(benzyl) or phenyl substituents at the phosphorus atom and the selenium atom of the P=Se group.