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Electrochemical Synthesis of gem-Difluoro- and γ-Fluoro-Allyl Boronates and Silanes.

ABSTRACT: The electrochemical synthesis of fluorinated allyl silanes and boronates was disclosed. The addition of electrogenerated boryl or silyl radicals onto many α-trifluoromethyl or α-difluoromethylstyrenes in an undivided cell allowed the formation of a large panel of synthetically useful gem-difluoro and γ-fluoroallyl boronates and silanes (64 examples, from 31 % to 95 % yield). In addition, a scale up of the reactions under continuous flow was showcased using an electrochemical reactor with promising volumetric productivity (688 g.L^-1 .h^-1 and 496 g.L^-1 .h^-1 ). Moreover, the synthetic utility of these building blocks was highlighted through versatile transformations. Finally, plausible reaction mechanisms were suggested to explain the formation of the products.

SUBMITTER: Aelterman M

PROVIDER: S-EPMC9828158 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Electrochemical Synthesis of gem-Difluoro- and γ-Fluoro-Allyl Boronates and Silanes.

Aelterman Maude M Biremond Tony T Jubault Philippe P Poisson Thomas T

Chemistry (Weinheim an der Bergstrasse, Germany) 20220926 66

The electrochemical synthesis of fluorinated allyl silanes and boronates was disclosed. The addition of electrogenerated boryl or silyl radicals onto many α-trifluoromethyl or α-difluoromethylstyrenes in an undivided cell allowed the formation of a large panel of synthetically useful gem-difluoro and γ-fluoroallyl boronates and silanes (64 examples, from 31 % to 95 % yield). In addition, a scale up of the reactions under continuous flow was showcased using an electrochemical reactor with promisi ...[more]

PMID: 36067044

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