Pyrazolato metal complexes - Synthesis, characterization, and X-ray crystal structures of heterotrimetallic Re-M-2 derivatives (M = Cu, Ag, Au)

By treating [(CO)(3)Re(Hpz)(2)(pz)] (Hpz = pyrazole) with [Cu(CH3CN)(4)]BF4 , AgNO3, or [Au(tht)Cl] (tht = tetrahydrothiophene) in acetonitrile in the presence of Et3N, the corresponding trinuclear complexes {(CO)(3)Re(pz)(3)[ M-(CH3CN)](2)} (1a-c) have been obtained. Treatment of complexes 1a-e with cyclohexyl isocyanide (c-CBH,INC) afforded the derivatives {(CO)(3)Re(pz)(3 )[M(c-C6H11NC)](2)} (2a-c). Complexes 2a-c have been characterized in solut ion by H-1-NMR spectroscopy and in the solid state by single-crystal X-ray diffraction analysis.