Nucleophilic additon of phosphine to 1-(tert-butyl)-4-vinylbenzene: a short-cut to bulky secondary and tertiary phosphines and their chalcogenides

Phosphine readily adds to 1-(tert-butyl)-4-vinylbenzene in the KOH–DMSO system (70–120°C, 3h, atmospheric pressure) to form bis[4-(tert-butyl)phenethyl]phosphine and tris[4-(tert-butyl)phenethyl]phosphine, which are further oxidized to corresponding phosphine oxides, sulfides and selenides.