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 μ-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.