CARBONYLATION AND HYDROGENATION OF cis-CH3Mn(CO)4L, SUBSTITUTIONAL REACTIVITY OF cis-HMn(CO)4L, AND BINUCLEAR ELIMINATION BETWEEN cis-CH3Mn(CO)4P(OPh)3 AND cis-HMn(CO)4P(OPh)3 (L = CO, PPh3, P(OPh)3, PBu3 AND P(OMe)3)

Article abstract of DOI:10.1016/0022-328X(86)82016-2

Several reactions of cis-CH3Mn(CO)4L and cis-HMn(CO)4L, have been investigated.The carbonylation of cis-CH3Mn(CO)4L (L = CO, P(OPh)3, P(OMe)3, and PBu3) shows a very small ligand effect, indicating a transition state that has little unsaturation.Reaction with H2 has very similar observed rate constants and activation parameters to the carbonylation.The hydrides, cis-HMn(CO)4L (L = P(OPh)3, PPh3 and PBu3), are remarkably unreactive toward substitution, requiring temperatures of 100 deg C.A radical mechanism is most likely.Reactions of cis-HMn(CO)4P(OPh)3 with cis-CH3Mn(CO)4P(OPh)3 and cis-HMn(CO)4PBu3 with CH3C(O)Mn(CO)5 occur at temperatures where methyl migration is readily established and the hydride complexes are unreactive.Thus methyl migration, followed by coordination to a bridging hydride, is indicated for these binuclear reductive elimination reactions.