Preparation, characterization, and properties of 1,1′-azo-o-carbaboranes

1-Amino-1,2-dicarbadodecaborane anions, o-RCB10H10CNH22–(R = H, Me, or Ph), are oxidized by K[MnO4] in liquid NH3 to give 1,1′-azo-o-carbaboranes, RCB10H10CNNCB10H10CR (3), whereas oxidation of HCB10H10CCB10H10CNH24– in the same solvent exclusively affords hydrazobis(o-carbaborane), HCB10H10CCB10H10CNHNHCB10H10CCB10H10CH. The reduction of (3) to the corresponding hydrazocarbaborane, RCB10H10CNHNHCB10H10CR (2), has been successfully achieved. closo-nido-Azocarbaboranes, RCB10H10CNNCB9H10CR–(4), and nido-nido ones, RCB9H10CNNCB9H10CR2–(5), have also been prepared by the degradation of (3) with K[OH]. Their structure and properties are discussed on the basis of spectroscopic data.