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Ir-Catalyzed Selective B(3)-H Amination of o-Carboranes with NH3
Yik Ki Au1, Jie Zhang1, Yangjian Quan1
1Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong, Shatin, N. T., Hong Kong, China.
Abstract:
Ammonia gas, NH3, is a cheap and widely used industrial feedstock, which has received tremendous research interests in its functionalization. This work reports a breakthrough in catalytic selective cage B(3)-H amination of o-carboranes with NH3 via Ir-catalyzed B-H/N-H dehydrocoupling, offering convenient and efficient access to a series of 3-NH2-o-carborane derivatives in moderate to high isolated yields with a broad substrate scope. The employment of readily available NH3 gas as the aminating reagent with H2 as the sole byproduct endows the protocol economy, practicability, and environmental friendliness. A plausible reaction mechanism is proposed on the basis of control experiments.
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