B3LYP calculations phosphate reactions

An ab initio and DFT study of the stereochemistry of desulfurization of cis- and /ra r-2,3-dimethylthiirane isomers by trimethyl phosphate was reported by Kalaiselvan and Venuvanalingam <2006JMT1>. In keeping with experimental results, their calculations indicated that the exothermic reaction is concerted and occurs by attack at sulfur. The completely stereospecific desulfurizations had activation energies of 28.6 and 26.7 kcal moH for the cis- and /ra r-isomers, respectively, at the B3LYP/6-31G(d) level of theory. 

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