Hydrolytic cleavage of paraoxon and parathion by oximate and functionalized oximate ions: A comparative study

Abstract

560-565<span style="font-size:11.0pt;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";mso-bidi-font-family:="" mangal;letter-spacing:-.1pt;mso-ansi-language:en-gb;mso-fareast-language:en-us;="" mso-bidi-language:hi"="" lang="EN-GB">Bimolecular reactions of O,O-diethyl-O-p-nitrophenylphosphate (paraoxon) and O,O-diethyl-O-p-nitrophenyl phosphorothioate (parathion) with oximate (pyridinealdoxime 2-PyOx- and 4-PyOx-) and its functionalized oximate, 4-(hydroxyimino)methyl)-1-alkylpyridinium bromide ions (alkyl = C10H21 (4-C10PyOx-); alkyl = C12H25 (4-C12PyOx-)) have been investigated in aqueous and cationic micellar media of cetylpyridinium bromide, cetyltrimethyl-ammonium bromide and cetyltetradecyltrimethylammonium bromide at pH 9.5 and 27 oC. Under the micellized condition, a 1.2×103 fold and 9.0×106 fold rate enhancement over the aqueous reaction of paraoxon (ko = 7.5×10-8 s-1) and parathion (ko = 9.5×10-11) is observed.</span