Lin Hung Shiu, Sue-Lein Wang, Rai-Shung Liu and Ming-Jung Wu
A tungsten–η1-vinylprop-2-ynyl compound undergoes enantioselective aminocarbonylation to afford an optically pure tungsten–π-γ-lactone; this π-allyl complex is useful for the efficient synthesis of optically pure α-methylene butyrolactone.