A quantum-chemical analysis of rearrangements in hydrophosphoryl compounds

The spatial structure and the energies of configurations corresponding to s tationary potential energy surface points for rt arrangements of various ph osphonous acid fluoro derivatives into phosphine oxide derivatives in the g as phase were calculated. The calculations were performed by the spin-restr icted Hartree-Fock-Roothaan method with the 6-31G** basis set, taking into account correlation effects at the level of many-particle Moller-Plesset se cond-order perturbation theory and by the density Functional method with a triple-zeta basis set. The prototropic rearrangement of some hydrophosphory l compounds was found to follow the bimolecular mechanism; tunneling prevai led at temperatures below 340 K. A compound whose two tautomerio forms were close to equilibrium was predicted.