Reactive Alkoxide Complexes of Groups 6 and 7 Metals

Easily available alkoxo complexes [M(OR)(CO) 3 (bipy)] (M = Mn, Re) and [Mo(OR)(η 3 -C 3 H 5 )(CO) 2 (phen)] react with dimethylacetylenedicarboxylate (DMAD) to afford the Z -alkenyls resulting from DMAD insertion into the M−OR bonds. Evidence suggesting a nondissociative mechanism is presented.