A Fluxional Cu8 H6 Cluster Supported by Bis(diphenylphosphino)methane and its Facile Reaction with CO2.

A copper hydride cluster [Cu8 (μ-H)6 (μ-dppm)5 ](PF6 )2 (dppm=bis(diphenylphosphino)methane) was prepared from reaction of [CuH(PPh3 )]6 with dppm in the presence of [Cu(CH3 CN)4 ]PF6 and exhibited fluxional behaviors in solution where the hydrides and the phosphines are scrambling around the trans-bicapped octahedral Cu8 framework. The Cu8 H6 complex showed facile reactivity with CO2 (1 atm, RT) to afford a tricopper complex, [Cu3 (μ-H)(μ-O2 CH)(μ-dppm)3 ]PF6 , which could be developed to unprecedented hydrosilylation of CO2 catalyzed by multinuclear CuH species under mild conditions.