Room Temperature Stable Organocuprate Copper(III) Complex

The paramagnetic trigonal-planar copper complexes {K(18C6)}[Cu-II(OC(CH3)(CF3)(2))(3)] (2) and K[Cu-II(OC(C6H5)(CF3)(2))(3)] (3) have been prepared and characterized, including X-ray crystallography, in 61% and 3% yields, respectively. The latter complex does not form preferentially, because CuBr2 and KOC(C6H5)(CF3)(2))(3) also form the diamagnetic complexes {K(18C6)}[K-2{Cu-I(OC(C6H5)(CF3)(2))(2)}(3)] (4) and {K(18C6)}[Cu-III(OC(C6H4)(CF3)(2))(2)] (5) These species were characterized by X-ray crystallography, UV-vis spectroscopy, H-1, C-13{H-1}, and F-19{H-1} NMR spectroscopy, and elemental analysis. The unique organocuprate Cu(III) species with {O2C2} coordination was formed by ortho metalation of two phenyl rings, resulting in trans-{O2C2} coordination of Cu(III), and is stable at room temperature in the solid state and in dark solutions of THF.