Theoretical Study of the Regioselectivity of the Reaction Between Diethyl(Trichloromethy1)Phosphonateand Triethylphosphite Using the DFT Method

Abstract

In this study we used the DFT/B3LYP/6-311G(d,p) quantum mechanical method to propose a theoretical explanation of the regioselectivity observed experimentally in the reaction between diethyl(trichloromethy1)phosphonate and triethylphosphite using a variety of approaches, notably frontier molecular orbital theory and calculation of activity energies and reactivity indices. Our results show that triethylphosphite functions as a nucleophile while diethyl(trichloromethy1) phosphonate behaves as an electrophile. The nucleophilic attack takes place preferentially at the chlorine atom of diethyl (trichloromethy1)phosphonate rather than at the carbon, and the reaction is polar and regioselective.

Theoretical study of the chemical reactivity of a class of trivalent phosphorus derivatives towards polyhaloalkanes: DFT study

“…Most polyhalomethanes such as tetrachloromethane CCl 4 [1], chloroform CHCl 3 [2,3], diethyl trichloromethyl phosphonate CCl 3 PO(OEt) 2 [4,5] and trichloromethylphosphine oxide CCl 3 PO(Ph) 2 [6] react with trialkylphosphites through the participation of a single halogen atom. However, dichloromethyl ether [7] and N-(trichloromethyl)-dialkylamine [8] which are highly electrophilic polyhaloalkanes can substitute two or even three of their halogen atoms with dialkylphosphonyl groups.…”