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Reduction of Activated Alkenes by P^III /P^V Redox Cycling Catalysis.

ABSTRACT: The carbon-carbon double bond of unsaturated carbonyl compounds was readily reduced by using a phosphetane oxide catalyst in the presence of a simple organosilane as the terminal reductant and water as the hydrogen source. Quantitative hydrogenation was observed when 1.0?mol?% of a methyl-substituted phosphetane oxide was employed as the catalyst. The procedure is highly selective towards activated double bonds, tolerating a variety of functional groups that are usually prone to reduction. In total, 25 alkenes and two alkynes were hydrogenated to the corresponding alkanes in excellent yields of up to 99?%. Notably, less active poly(methylhydrosiloxane) could also be utilized as the terminal reductant. Mechanistic investigations revealed the phosphane as the catalyst resting state and a protonation/deprotonation sequence as the crucial step in the catalytic cycle.

SUBMITTER: Longwitz L

PROVIDER: S-EPMC7027467 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Reduction of Activated Alkenes by PIII /PV Redox Cycling Catalysis.

Longwitz Lars L Werner Thomas T

Angewandte Chemie (International ed. in English) 20200121 7

The carbon-carbon double bond of unsaturated carbonyl compounds was readily reduced by using a phosphetane oxide catalyst in the presence of a simple organosilane as the terminal reductant and water as the hydrogen source. Quantitative hydrogenation was observed when 1.0 mol % of a methyl-substituted phosphetane oxide was employed as the catalyst. The procedure is highly selective towards activated double bonds, tolerating a variety of functional groups that are usually prone to reduction. In to ...[more]

PMID: 31793147

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