A preliminary quantum‐chemical study of the mechanisms for the reactions of perchlorofluoroethanes with nucleophiles initiated by chlorophilic attacks

A preliminary theoretical study of the mechanisms for the reactions of the perchlorofluoroethanes CF2ClCCl3 (1), CF2ClCCl2F (2) and CF3CCl3 (3), with nucleophiles has been carried out by the MNDO method, following the experimentally suggested process shown in Scheme 1. The unlikely chlorophilic attack in the first step of Scheme 1 has been shown to be feasible for 1, 2 and 3 by analysis of the MO interactions. The second step has been found to be affected by the anionic hyperconjugation which stabilizes the anions CF2ClCCl (4), CF2ClCClF− (5) and CF3CCl (6) and would make reactions (2) (the second step) unfeasible in gas phase, but in solution reaction (2) may still easily occur for 4 and 5.