Clusters (Ma(GaCp*)b(CNR)c) (M = Ni, Pd, Pt): Synthesis, Structure, and Ga/Zn Exchange Reactions

Reactions of homoleptic isonitrile ligated complexes or clusters of d(10)-metals with the potent carbenoid donor ligand GaCp* are presented (Cp* = pentamethyl-cyclopentadienyl). Treatment of [Ni-4(CNt-Bu)(7)], [{M-(CNR)(2)}(3)] (M Pd, Pt) and [Pd(CNR)(2)Me-2] (R = t-Bu, Ph) with suitable amounts of GaCp* lead to the formation of the heteroleptic, tri- and tetranuclear clusters [Ni-4(CNt-Bu)(2)(GaCp*)(3)] (1), [{M(CNt-Bu)}(3)(GaCp*)(4)] (M = Pd: 2a, Pt: 2b), and [{Pd(CNR)}(4)(GaCp*)(4)] (R = t-Bu: 3a, Ph: 3b). The reactions involve isonitrile substitution reactions, GaCp* addition reactions, and cluster formation reactions. The new compounds were investigated for their ability to undergo Ga/Zn exchange reactions when treated with ZnMe2. The novel tetranuclear Zn-rich clusters [Ni4GaZn2(Cp*)(2)Me-7(CNt-Bu)(6)] (4) and [{Pd(CNR)}(4)(ZnCp*)(4)(ZnMe)4] (R = t-Bu: 5a, Ph: 5b) were obtained and isolated. The electronic situation and geometrical arrangement of atoms of all compounds will be presented and discussed. All new compounds are characterized by solution H-1, C-13 NMR and IR spectroscopy, elemental analysis (EA), liquid injection field desorption ionization mass spectrometry (LIFDI-MS) as well as single crystal X-ray crystallography.