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Silver-Catalyzed Enantioselective Propargylation Reactions of N-Sulfonylketimines.

ABSTRACT: The enantioselective silver-catalyzed propargylation of N-sulfonylketimines is described. This reaction proceeds in high yield and excellent enantiomeric ratio and is compatible with a wide variety of diaryl- and alkylketimines. Synthetic transformations of homopropargylic products via enyne ring-closing metathesis, Sonogashira cross-coupling, and reduction reactions proceed with high stereochemical fidelity. Both allenyl and propargyl borolane reagents can be used to obtain homopropargylic products, a distribution most consistent with a mechanism involving transmetalation of the silver catalyst with the borolane reagent.

SUBMITTER: Osborne CA

PROVIDER: S-EPMC4962794 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Silver-Catalyzed Enantioselective Propargylation Reactions of N-Sulfonylketimines.

Osborne Charlotte A CA Endean Thomas B D TB Jarvo Elizabeth R ER

Organic letters 20151027 21

The enantioselective silver-catalyzed propargylation of N-sulfonylketimines is described. This reaction proceeds in high yield and excellent enantiomeric ratio and is compatible with a wide variety of diaryl- and alkylketimines. Synthetic transformations of homopropargylic products via enyne ring-closing metathesis, Sonogashira cross-coupling, and reduction reactions proceed with high stereochemical fidelity. Both allenyl and propargyl borolane reagents can be used to obtain homopropargylic prod ...[more]

PMID: 26506430

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