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Hydrogenation of Secondary Amides using Phosphane Oxide and Frustrated Lewis Pair Catalysis.

ABSTRACT: The metal-free catalytic hydrogenation of secondary carboxylic acid amides is developed. The reduction is realized by two new catalytic reactions. First, the amide is converted into the imidoyl chloride by triphosgene (CO(OCCl₃ )₂ ) using novel phosphorus(V) catalysts. Second, the in situ generated imidoyl chlorides are hydrogenated in high yields by an FLP-catalyst. Mechanistic and quantum mechanical calculations support an autoinduced catalytic cycle for the hydrogenation with chloride acting as unusual Lewis base for FLP-mediated H₂ -activation.

SUBMITTER: Koring L

PROVIDER: S-EPMC8596796 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Hydrogenation of Secondary Amides using Phosphane Oxide and Frustrated Lewis Pair Catalysis.

Köring Laura L Sitte Nikolai A NA Bursch Markus M Grimme Stefan S Paradies Jan J

Chemistry (Weinheim an der Bergstrasse, Germany) 20210902 57

The metal-free catalytic hydrogenation of secondary carboxylic acid amides is developed. The reduction is realized by two new catalytic reactions. First, the amide is converted into the imidoyl chloride by triphosgene (CO(OCCl<sub>3</sub> )<sub>2</sub> ) using novel phosphorus(V) catalysts. Second, the in situ generated imidoyl chlorides are hydrogenated in high yields by an FLP-catalyst. Mechanistic and quantum mechanical calculations support an autoinduced catalytic cycle for the hydrogenation ...[more]

PMID: 33460471

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