Cationic Copper Hydride Clusters Arising from Oxidation of (PhP)CuH.

Transfer of the first electron from (PhP)CuH to CpFe is fast (k > 10 L·mol·s). Transfer of a second electron to the same oxidant has a much lower thermodynamic driving force and is considerably slower, with k = 9.29(4) × 10 L·mol·s. The second oxidation leads to the formation of [(PhP)CuH]. The structure of [(PhP)CuH] has been confirmed by its conversion back to (PhP)CuH and by microanalysis; X-ray diffraction shows that the complex is a bitetrahedron in the solid state. [(PhP)CuH] can also be prepared by treating (PhP)CuH with MeOTf. With less than 1 equiv of CpFe as oxidant, (PhP)CuH gives [(PhP)CuH] as the major product; X-ray diffraction shows a Cu octahedron with one face capped by an additional Cu. [(PhP)CuH] can also be prepared by treating (PhP)CuH with [Cu(CHCN)] (along with 1 equiv of PhP), and can be converted back to (PhP)CuH with base/H.