REACTIONS OF ORGANOSTANNANES CATALYZED BY A PALLADIUM-IMINOPHOSPHINE COMPLEX

A palladium complex coordinated by an iminophosphine ligand was disclo sed to be a remarkably active catalyst for the coupling of organostann anes with aryl halides. The mechanistic studies show that the reaction of. an alkynylstannane proceeds tl;rough a novel catalytic cycle whic h involves an oxidative addition of the organostannane to a Pd(0)-imin ophosphine complex. This oxidative adduct was demonstrated to react wi th alkynes to give carbostannylation products. The catalyst could also mediate the homocoupling reaction of organostannanes using air or all yl acetate as a mild and easily available oxidant.