Triosmium Carbonyl Clusters Containing a Mixture of Dppm and Dppe Ligands

Abstract

Four osmium carbonyl complexes were synthesized via microwave heating by reacting either Os3(CO)12 or Os3(CO)10( $$\mu$$ -dppm) with dppe, where dppm = bis(diphenylphosphino)methane and dppe = 1,2-bis(diphenylphosphino)ethane. Two of the complexes, Os3(µ-dppe)(CO)8(dppe) (1) and Os3(µ-dppm)(CO)8(dppe) (2), are the first examples of triangular triosmium clusters containing diphosphane ligands that exhibit both bridging and chelating coordination modes in the same molecule. Complexes 2 and [Os3(µ-dppm)(CO)9]2(µ-dppe) (3) are the first examples of triosmium clusters containing two different diphosphane ligands in the same molecule. Complexes 3 and [Os3(µ-dppe)(CO)9]2(µ-dppe) (4) are hexanuclear clusters containing two triangular Os3 units linked together by a bridging diphosphane ligand. Crystal structures for complexes 1–3 are reported. Two trinuclear cluster complexes, Os3(μ-dppe)(CO)8(dppe) (1) and Os3(μ-dppm)(CO)8(dppe) (2), and two hexanuclear cluster complexes, [Os3(μ-dppm)(CO)9]2(μ-dppe) (3) and [Os3(μ-dppe)(CO)9]2(μ-dppe) (4), were synthesized and characterized by X-ray crystal diffraction. Complexes 2 and 3 are the first examples of triangular triosmium clusters containing two different diphosphane ligands in the same molecule.