Structure and bonding in redox-active d4, d5 and d6 alkyne complexes: metal–alkyne moieties as electron sinks
Abstract
X-Ray structural studies of the two redox-related pairs [Cr(CO)2(η-PhCCPh)(η6-C6HMe5)]0/1+ and [Mo(CO)2(η-PhCPh)(Tp′)]0/1+[Tp′= hydrotris(3,5-dimethyl-pyrazolyl)borate] are consistent with the HOMO of the d6, Cr0 alkyne complex being an antibonding M–alkyne π⊥ orbital.