Room Temperature Stable Organocuprate Copper(III) Complex

The paramagnetic trigonal-planar copper complexes {K­(18C6)}­[Cu<sup>II</sup>(OC­(CH<sub>3</sub>)­(CF<sub>3</sub>)<sub>2</sub>)<sub>3</sub>] (<b>2</b>) and K­[Cu<sup>II</sup>(OC­(C<sub>6</sub>H<sub>5</sub>)­(CF<sub>3</sub>)<sub>2</sub>)<sub>3</sub>] (<b>3</b>) have been prepared and characterized, including X-ray crystallography, in 61% and 3% yields, respectively. The latter complex does not form preferentially, because CuBr<sub>2</sub> and KOC­(C<sub>6</sub>H<sub>5</sub>)­(CF<sub>3</sub>)<sub>2</sub>)<sub>3</sub> also form the diamagnetic complexes {K­(18C6)}­[K<sub>2</sub>{Cu<sup>I</sup>(OC­(C<sub>6</sub>H<sub>5</sub>)­(CF<sub>3</sub>)<sub>2</sub>)<sub>2</sub>}<sub>3</sub>] (<b>4</b>) and {K­(18C6)}­[Cu<sup>III</sup>(OC­(C<sub>6</sub>H<sub>4</sub>)­(CF<sub>3</sub>)<sub>2</sub>)<sub>2</sub>] (<b>5</b>). These species were characterized by X-ray crystallography, UV–vis spectroscopy, <sup>1</sup>H, <sup>13</sup>C­{<sup>1</sup>H}, and <sup>19</sup>F­{<sup>1</sup>H} NMR spectroscopy, and elemental analysis. The unique organocuprate Cu­(III) species with {O<sub>2</sub>C<sub>2</sub>} coordination was formed by ortho metalation of two phenyl rings, resulting in <i>trans</i>-{O<sub>2</sub>C<sub>2</sub>} coordination of Cu­(III), and is stable at room temperature in the solid state and in dark solutions of THF.