Transition Metal Catalyzed Direct Amination of the Cage B(4)–H Bond in o-Carboranes: Synthesis of Tertiary, Secondary, and Primary o-Carboranyl Amines

Transition metal catalyzed regioselective amination of the cage B(4)–H bond in o -carboranes has been achieved for the first time using O -benzoyl hydroxylamines or organic azides as the amination reagents, leading to the preparation of a series of tertiary and secondary carboranyl amines. Both amination reactions proceeded under mild conditions without the addition of any external oxidants. Hydrogenolysis of the resultant product 4-N(CH 2 Ph) 2 - o -carborane afforded the primary carboranyl amine, 4-amino- o -carborane, in quantitative yield.