Df. Brougham et al., AB-INITIO MOLECULAR-ORBITAL AND EXPERIMENTAL STUDIES OF HYDRIDE ADDITION TO PHOSPHINE-SUBSTITUTED MANGANESE CARBONYL-COMPLEXES, Organometallics, 14(1), 1995, pp. 151-156
Ab initio molecular orbital calculations on [Mn(CO)(6)](+), [Mn(CO)(5)
(PH3)](+), and the formyl and hydride complexes derived from these sho
w that the increased stability of cis-Mn(CO)(4)(PR(3))(CHO) and simila
r formyl complexes is largely kinetic in origin. The transition state
for the unsubstituted formyl complex, which forms the corresponding hy
dride by a simple dissociative mechanism, differs from the transition
states for the substituted formyl complexes, which form the correspond
ing hydrides by concerted mechanisms. Experimental studies of hydride
addition to diphenylphosphinoalkane-substituted hexacarbonylmanganese
cations are in accord with the theoretical conclusions.