The unusual structure of the novel [Mo2Cp2Cl5]– ion (Cp = C5H5)
Abstract
The novel [Mo2Cp2Cl5]– ion (Cp = C5H5), obtained as the salt of the bis(triphenylphosphine)iminium (PPN) cation on reacting MoCpCl2 with PPN+Cl– in CH2Cl2, contains two equivalent molybdenum centres at a distance of 2.413(1)Å, which are bonded to two terminal Cl atoms and one η5-C5H5 group and are bridged by a single Cl ligand; the electronic structure indicates a metal-metal triple bond, which is little perturbed by the bridging chloride ligand; the molecule provides a bridge between two diverse structures of M2(η5-C5H4Pri)2Cl4(M = Mo: quad ruply-bridged, Mo–Mo single bond; M = W: unbridged, W–W triple bond).