RELATIVE ENERGIES OF METHYLPHOSPHOLES AND VINYLPHOSPHOLES

The geometries of all isomers of methylphosphole and three isomers of vinylphosphole (1-vinyl-1H-phosphole, 2-vinyl-2H-phosphole, and 3-vinyl-3H-phosphole) were completely optimized at the HF/6-31G* level. The phosphole ring is minimally perturbed by the substituents. The relative energies of these compounds suggest that substitution is preferred upon phosphorus over carbon to minimize steric interactions between the substituent and the phosphole ring.