CONFORMATIONS OF MUSTARD SULFOXIDE AND MUSTARD SULFONE

Sulfur mustard, bis-(2-chloroethyl)sulfide, has been one of the most commonly used chemicals for chemical warfare since its introduction in World War 1. Decontamination procedures usually involve the oxidation to the corresponding sulfoxide or sulfone. Computational methods were used to identify the most stable conformations and determine their relative energies. The most stable sulfone, determined by Hartree Fock, post Hartree Fock, and density functional methods, was the all trans conformation. For the sulfoxide, the all trans conformer was the most stable by HF and DFT methods; whereas, by MP2 the most stable was the conformation with the chlorides turned away from the lone oxygen.