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Electron-Transfer and Hydride-Transfer Pathways in the Stoltz-Grubbs Reducing System (KOtBu/Et₃ SiH).

ABSTRACT: Recent studies by Stoltz, Grubbs et al. have shown that triethylsilane and potassium tert-butoxide react to form a highly attractive and versatile system that shows (reversible) silylation of arenes and heteroarenes as well as reductive cleavage of C-O bonds in aryl ethers and C-S bonds in aryl thioethers. Their extensive mechanistic studies indicate a complex network of reactions with a number of possible intermediates and mechanisms, but their reactions likely feature silyl radicals undergoing addition reactions and S_H 2 reactions. This paper focuses on the same system, but through computational and experimental studies, reports complementary facets of its chemistry based on a) single-electron transfer (SET), and b) hydride delivery reactions to arenes.

SUBMITTER: Smith AJ

PROVIDER: S-EPMC5656899 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Electron-Transfer and Hydride-Transfer Pathways in the Stoltz-Grubbs Reducing System (KOtBu/Et3 SiH).

Smith Andrew J AJ Young Allan A Rohrbach Simon S O'Connor Erin F EF Allison Mark M Wang Hong-Shuang HS Poole Darren L DL Tuttle Tell T Murphy John A JA

Angewandte Chemie (International ed. in English) 20171002 44

Recent studies by Stoltz, Grubbs et al. have shown that triethylsilane and potassium tert-butoxide react to form a highly attractive and versatile system that shows (reversible) silylation of arenes and heteroarenes as well as reductive cleavage of C-O bonds in aryl ethers and C-S bonds in aryl thioethers. Their extensive mechanistic studies indicate a complex network of reactions with a number of possible intermediates and mechanisms, but their reactions likely feature silyl radicals undergoing ...[more]

PMID: 28892585

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