Synthesis of asymmetric heterotrimetallic gold clusters containing Mo, W, and Mn

Abstract

A series of new heterotrimetallic gold clusters, [(OC)₃M(μ-S₂CPR₃)(μ-AuPPh₃)Mo(CO)₃] (M = Mn, R = Cy, 3a; R = Prⁱ, 3b; M = Re, R = Cy, 3c; R = Prⁱ, 3d) and [(L)(OC)₂Mo(μ-S₂CPCy₃)(μ-AuPPh₃)M′(CO)₃] (M′ = Mo, L = η³-allyl, 6a; L = NO, 6b; M′ = W, L = η³-allyl, 6c; L = NO, 6d), have been synthesized in good yields by the reactions of ClAuPPh₃ with the corresponding homo- or heterobinuclear anions, [(OC)₃M(μ-S₂CPR₃)Mo(CO)₃]⁻ and [(L)(OC)₂Mo(μ-S₂CPCy₃)M′(CO)₃]⁻, formed respectively by the reduction of the complexes [(OC)₃M(μ-Br)(μ-S₂CPR₃)Mo(CO)₃] and [(L)(OC)₂Mo(μ-Br)(μ-S₂CPR₃)M′(CO)₃] with Na/Hg. The new complexes have been characterized spectroscopically and the molecular structures of 3a, 6a, and 6c have been determined by X-ray crystallography, revealing remarkable structural differences between the trimetallic cores.