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Nickel(ii)-catalyzed reductive silylation of alkenyl methyl ethers for the synthesis of alkyl silanes.

ABSTRACT: A new one pot protocol has been developed for the reductive silylation of alkenyl methyl ethers using Et₃Si-BPin and HSiEt₃ with nickel(ii) catalyst. Styrene type methyl ethers, multi-substituted vinyl methyl ethers, heterocycles and unconjugated vinyl ethers are all tolerated to form alkyl silanes. Mechanistic study reveals that it is a cascade of a C-O bond silylation and vinyl double bond hydrogenation process. Internal nucleophilic substitution or oxidative addition pathways were both acceptable for C-O bond cleavage. The acquired intermediate alkenyl silanes then proceeded through an unconventional reduction process thus providing alkyl silanes.

SUBMITTER: Qiu X

PROVIDER: S-EPMC9043817 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Nickel(ii)-catalyzed reductive silylation of alkenyl methyl ethers for the synthesis of alkyl silanes.

Qiu Xiaodong X Zhou Li L Wang Haoran H Lu Lingyi L Ling Yong Y Zhang Yanan Y

RSC advances 20211118 59

A new one pot protocol has been developed for the reductive silylation of alkenyl methyl ethers using Et<sub>3</sub>Si-BPin and HSiEt<sub>3</sub> with nickel(ii) catalyst. Styrene type methyl ethers, multi-substituted vinyl methyl ethers, heterocycles and unconjugated vinyl ethers are all tolerated to form alkyl silanes. Mechanistic study reveals that it is a cascade of a C-O bond silylation and vinyl double bond hydrogenation process. Internal nucleophilic substitution or oxidative addition pat ...[more]

PMID: 35496447

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