Efficient halogenation of unsaturated organoaluminum compounds with sulfonyl halides

Abstract

Alkenylalumanes prepared by carbo-or cycloalumination of substituted acetylenes reacted with an equivalent amount of sulfonyl halide (MsCl, TsCl, PhSO2Cl, MsBr) in methylene chloride or hexane at room temperature to produce alkenyl halides in high yields. Electron-donor solvents such as diethyl ether or tetrahydrofuran inhibited the halogenation process. β-Substituted vinylalumanes generated by hydroalumination of substituted acetylenes failed to react with sulfonyl halides.