Reactions of group IV organometallic compounds XXV. Preparations and reactions of tetramethylene-[(α-trimethylsilyl- or α-trimethylstannyl)phenacyl]sulphonium salts and ylides

Article abstract of DOI:10.1016/S0022-328X(00)88286-8

Tetramethylene[(α-trimethylsilyl- and α-trimethylstannyl)phenacyl]sulphonium salts [(CH₂)₄S⁺CH(MMe₃)COPh]Cl^- (M = Si and Sn) have been prepared by the reaction of tetramethylenesulphonium phenacyclide (I) with the relevant Me₃MCl. The thermal rearrangement of tetramethylene[(α-trimethylsilyl)phenacyl]sulphonium chloride (II) unexpectedly afforded Cl(CH₂)₄SCHC(OSiMe₃)Ph (III) by a 1,3-migration of the trimethylsilyl group to the oxygen atom accompanied by simultaneous ring-opening. Tetramethylene[(α-trimethylstannyl)phenacyl]sulphonium chloride (IV) gave the corresponding ylide (VI) by reaction with n-butyllithium.