New applications of the frontal steric effect model. Steric aspects of theWilliamson reaction mechanism in the series of chloromethylphosphine oxides

Fine steric aspects of the Williamson reaction in the series of chloromethy lphosphine oxides were analyzed on the basis of a modified frontal steric e ffect model and experimental kinetic data. The structure of the activated c omplex is determined by the initial conformation of chloromethylphopshine o xide, which in turn depends on steric requirements of substituents on the p hosphorus. This conclusion is confirmed by the results of quantum-chemical calculations.