Hückel Molecular Orbital Models for Heterocycles with Tetra-coordinated Phosphorus Atoms

Abstract

MANY heterocyclic compounds with tetra-coordinated phosphorus atoms have been synthesized1,2. Several models for Hukel molecular orbital calculations3–6 have been proposed for heterocycles containing atoms with d-orbitals, but the most suitable model should first be found before such calculations are made for these phosphorus heterocycles. The most suitable model can be found by comparing the experimental data for phosphabenzene (more exactly 1,1-diphenylphosphabenzene)1,7,8 with the Hukel parameters calculated for all these models.