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Mg-Catalyzed Nucleophilic Cage B-H Amination of o-Carborane
Jie Zhang1, Qihang Zhuo2, Chen Huang1
1Department of Chemistry, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, 00000, China.
Abstract:
A magnesium-catalyzed regioselective nucleophilic cage B(4)-H monoamination or B(4,11)-H diamination of 1,2-diaryl-o-carboranes was developed. Utilizing magnesium hydride (MgH2) as a precatalyst and secondary amines as a nitrogen source, a formal dehydrogenative N-H/B-H cross-coupling proceeded smoothly to afford a series of cage B(4)-monoaminated or B(4,11)-diaminated o-carboranes. A reaction mechanism was proposed with in situ-generated amino magnesium species as the reactive nucleophile and catalyst. This transformation offered a cost-effective, environmentally benign, and sustainable strategy for carborane cage BH amination.
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One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.

