Two Tetracobalt Cluster Complexes: Preparation and Molecular Structures of Co4(μ-dppm)2(μ-CO)3(CO)5 and CO4(μ-CO)3(CO)6(η-C6H6)

Abstract

The crystal and molecular structures of the title complexes (1) and (2) are described. Each contains a Co₄ tetrahedron, one face of which is edge-bridged by three -CO ligands. In (1), a pair of mutually orthogonal Co–Co bonds are bridged by the two dppm (dppm = bis(diphenylphosphino)methane) ligands. The structure of the benzene complex was determined at 153 and 300 K; as with other arene–Co₄ clusters, the η⁶-benzene ligand sits on the apical (i.e. non-CO-bridged) Co atom.

Manuscript received: 25 June 2001.

Final version: 20 August 2001.