… rate-limiting proton transfer to sulfur with nucleophilic attack at phosphorus-A new proposed mechanism for hydrolytic decomposition of the P= S pesticide, Diazinon, …

D Churchill, JM Dust, E Buncel

Index: Churchill, Doreen; Dust, Julian M.; Buncel, Erwin Canadian Journal of Chemistry, 2007 , vol. 85, # 6 p. 421 - 431

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Citation Number: 12

Abstract

We report herein the first kinetic study of a P= S containing organophosphorus pesticide, Diazinon (1), in the moderately concentrated acid region. Product analyses (31P NMR) show that reaction occurs only at the P centre. The rate-acidity profile (k obs vs. molarity of H2SO4) appears as a curve in which the initial slight downward trace (molarity= 1 to ca. 5) is followed by sharper upward curve (molarity ca. 5 to 14). Using treatments involving the ...