Reaction pathways for gas-phase hydrolysis of formyl compounds HXCO (X = H, F, and Cl)

Abstract

Formation and decomposition of the adduct species CHX(OH) 2 , where X=H, F, and Cl, have been studied by means of ab initio molecular orbital theory. Equilibrium geometries and transition structures have been fully optimized with 6-31G * and 6-311G ** basis sets at the Hartree-Fock and second-order MOller-Plesset perturbation levels of theory. Heats of reaction and barrier heights have been computed with MOller-Plesset theory up to full fourth order using the 6-311++G ** basis. Addition of H 2 O to HXCO yields CHX(OH) 2 which then decomposes preferentially by 1,2-elimination of HX to give formic acid as a product. Other higher energy paths, including 1,2-elimination of H 2 and the involvement of carbene species, are of negligible significance