Formal net charges, bond populations, atomic orbital coefficients, energy components and conformation of dimethyl-2, 2-dichlorovinylphosphate have been studied theoretically by using the CNDO/2 molecular orbital calculation method in attempt to describe the reactivity and the stability of the molecule.
From the analysis of rate equation, molecular orbital calculations and identification of the hydrolysis products, 2,2-dichloroacetaldehyde and dimethylphosphoric acid, a mechanism of the hydrolysis of dimethyl-2,2-dichlorovinylphosphare (DDVP) has been proposed.
The hydrolysis of DDVP proceeds through the mechanism of nucleophilic addition, typical Micheal reaction in basic media. Therefore, it appears probable that the attack by strong nucleophile, hydroxide ion occurs at the increased positive charge C₂ (α) atom of a staggered conformation due to the inductive effect (-)I$gt;(+)R of 2,2-dichlorovinyl, electron-attracting group. And then, the hydrolytic scission involves the Ca (α)-O₃, π-anti-bonding orbital (π*) in the subsequent reaction in aqueous solution.
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