Reaction of Dichlorvos, dichloroacetaldehyde and related compounds with nucleophiles and phenols

Model compounds are used to demonstrate functional group reactivity of dimethyl-2,2-dichlorovinyl phosphate (DDVP, Dichlorvos or Vapona) towards amino compounds, phenols and thiols. Methylation of thiols occurs as a result of a trans- methylation reaction by DDVP. In aqueous media, the dichlorovinyl portion of the DDVP molecule is converted predominantly to dichloroacetaldehyde (DCA), in the absence of added nucleophile. The reactions of DCA with thiols, amino acid, and phenols are reported and mechanisms are suggested. 1,1-Dichloroacetone and methyl dichloroacetate were also used as model compounds to provide a greater insight into the reactivity of the dichloro-moiety of DDVP and DCA.