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Metal-Free C-H Borylation of N-Heteroarenes by Boron Trifluoride.

ABSTRACT: Organoboron compounds are essential reagents in modern C-C coupling reactions. Their synthesis via catalytic C-H borylation by main group elements is emerging as a powerful tool alternative to transition metal based catalysis. Herein, a straightforward metal-free synthesis of aryldifluoroboranes from BF₃ and heteroarenes is reported. The reaction is assisted by sterically hindered amines and catalytic amounts of thioureas. According to computational studies the reaction proceeds via frustrated Lewis pair (FLP) mechanism. The obtained aryldifluoroboranes are further stabilized against destructive protodeborylation by converting them to the corresponding air stable tetramethylammonium organotrifluoroborates.

SUBMITTER: Iashin V

PROVIDER: S-EPMC7702085 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Metal-Free C-H Borylation of N-Heteroarenes by Boron Trifluoride.

Iashin Vladimir V Berta Dénes D Chernichenko Konstantin K Nieger Martin M Moslova Karina K Pápai Imre I Repo Timo T

Chemistry (Weinheim an der Bergstrasse, Germany) 20200929 61

Organoboron compounds are essential reagents in modern C-C coupling reactions. Their synthesis via catalytic C-H borylation by main group elements is emerging as a powerful tool alternative to transition metal based catalysis. Herein, a straightforward metal-free synthesis of aryldifluoroboranes from BF<sub>3</sub> and heteroarenes is reported. The reaction is assisted by sterically hindered amines and catalytic amounts of thioureas. According to computational studies the reaction proceeds via f ...[more]

PMID: 32478432

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