Carbonyl substitution of the dicobalt-iron complex (μ3-S)FeCo2(CO)9 with monophosphane or diphosphane ligands

Abstract

Eight new dicobalt-iron clusters have been synthesised and structurally characterized. Treatment of (μ3-S)FeCo2(CO)9 (A) with monophosphane ligands tris(4-fluorophenyl)phosphane, tris(4-methoxyphenyl)phosphane, or tris(2-furyl)phosphane in the presence of Me3NO∙2H2O afforded monosubstituted complexes (μ3-S)FeCo2(CO)8L [L = P(4-C6H4F)3, 1; P(4-C6H4OMe)3, 3; P(2-C4H3O)3, 5] and disubstituted complexes (μ3-S)FeCo2(CO)7L2 [L = P(4-C6H4F)3, 2; P(4-C6H4OMe)3, 4; P(2-C4H3O)3, 6]. Reaction of complex A with Ph2PN[CH(CH3)2]PPh2 in refluxing toluene gave complex (μ3-S)FeCo2(CO)7{Ph2PN[CH(CH3)2]PPh2} (7) with an intramolecular bridging diphosphane ligand. Reaction of complex A with trans-1,2-bis(diphenylphosphino)ethylene (trans-dppv) and Me3NO∙2H2O yielded complex [(μ3-S)FeCo2(CO)8]2(trans-Ph2PCH = CHPPh2) (8) with an intermolecular bridging diphosphane ligand. The new complexes 1–8 were characterized by elemental analysis, IR, 1H NMR, 31P{1H} NMR, and 13C{1H} NMR spectroscopy, particularly for 1, 3, and 6–8 by X-ray crystallography.