The mass spectra of alkyl sulphones

Abstract

In contrast to the electron-impact induced fragmentation of sulphides which in the main orginates from ionisation of sulphur, the alkyl sulphones give fragments resulting from ionisation at oxygen. The major fragments arise from direct cleavage of the C–S bond to give R⁺ and RSO₂⁺, cleavage of the γ-bond to give (a) R·S(:O)(:[graphic omitted]H₂, and a single or double hydrogen rearrangement to give the species (b) R·S(OH)(:O·⁺) and (c) R·S(OH)(:O⁺H), respectively. The changes observed in the intensity of (b) and (c) with increasing size of R suggests that the β- and γ-carbon atoms are the sites of the hydrogen atoms involved in the production of species (c).