Nickel-catalyzed regioselective B(3,4,5,6)-H tetra-alkylation of o-carboranes

作     者：Jianwei Zhao Zuowei Xie 

作者机构：Department of Chemistry and State Key Laboratory of Synthetic ChemistryThe Chinese University of Hong KongHong Kong 999077China Shenzhen Grubbs Institute and Department of ChemistrySouthern University of Science and TechnologyShenzhen 518055China 

出 版 物：《Science China Chemistry》 (中国科学（化学英文版）)

年 卷 期：2023年第66卷第10期

页      面：2836-2841页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 070303[理学-有机化学] 0703[理学-化学] 

基　　金：supported by the Research Grants Council of the Hong Kong Special Administration Region (SRFS20214S05) 

主　　题：nickel catalysis B-H activation carborane alkylation regioselectivity 

摘      要：Though transition metal-catalyzed cage BH methylation has been well documented, catalytic alkylation of cage BH bonds remained elusive because transition metal alkyl complexes are prone to undergo β-H elimination. We report herein a highly efficient 8-aminoquinoline-assisted nickel-catalyzed regioselective cage B(3,4,5,6)-H tetra-alkylation of o-carboranes employing unactivated alkyl bromides as alkylating agents in the absence of any oxidants, leading to the preparation of a class of tetra-alkylated o-carboranes with a broad substrate scope in good to very high yields. This method opens new avenues for oxidant-free, direct, efficient, sustainable, and regioselective multiple B–H alkylation of carboranes via base metal catalysis.