Theoretical study of structural patterns in CH2OP2 isomers

DFT calculations have been performed on the derivatives of formula CH2OP2 to determine their total energy, the relative energy between the isomers and their geometry. Among compounds with a P-C-P linkage, the most stable one is the 2-hydroxy-1,2-diphosphirene II.1, a three-membered heterocycle with a P=C unsaturation. The phosphavinylidene(oxo)phosphorane HP=C=P(O)H IV.5 (which has the same skeleton as the experimentally obtained Mes*P=C=P(O)Mes*) lies 36.30 kcal mol-1 above it. The least stable compounds are carbenes; the singlet carbenes are more stable than the triplet ones.