Cyclic (Alkyl)(amino)carbene Ligand-Promoted Nitro Deoxygenative Hydroboration with Chromium Catalysis: Scope, Mechanism, and Applications

Autor:	Xiaoming Zeng, Gongda Deng, Lixing Zhao, Chenyang Hu, Meiming Luo, Xuefeng Cong, Liu Leo Liu
Rok vydání:	2021
Předmět:	chemistry.chemical_classification Ligand Hydride General Chemistry 010402 general chemistry 01 natural sciences Biochemistry Combinatorial chemistry Catalysis 0104 chemical sciences chemistry.chemical_compound Hydroboration Colloid and Surface Chemistry chemistry Nitro Carbene Deoxygenation Alkyl
Zdroj:	Journal of the American Chemical Society. 143:1618-1629
ISSN:	1520-5126 0002-7863
DOI:	10.1021/jacs.0c12318
Popis:	Transition metal catalysis that utilizes N-heterocyclic carbenes as noninnocent ligands in promoting transformations has not been well studied. We report here a cyclic (alkyl)(amino)carbene (CAAC) ligand-promoted nitro deoxygenative hydroboration with cost-effective chromium catalysis. Using 1 mol % of CAAC-Cr precatalyst, the addition of HBpin to nitro scaffolds leads to deoxygenation, allowing for the retention of various reducible functionalities and the compatibility of sensitive groups toward hydroboration, thereby providing a mild, chemoselective, and facile strategy to form anilines, as well as heteroaryl and aliphatic amine derivatives, with broad scope and particularly high turnover numbers (up to 1.8 × 106). Mechanistic studies, based on theoretical calculations, indicate that the CAAC ligand plays an important role in promoting polarity reversal of hydride of HBpin; it serves as an H-shuttle to facilitate deoxygenative hydroboration. The preparation of several commercially available pharmaceuticals by means of this strategy highlights its potential application in medicinal chemistry.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::68ea8d0f05ccde464dab3a0ce6d32c1b https://doi.org/10.1021/jacs.0c12318 Zobrazit plný text záznamu