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Asymmetric synthesis of 4,5,6- and 3,4,5,6-substituted azepanes by a highly diastereoselective and enantioselective lithiation-conjugate addition sequence.

ABSTRACT: Asymmetric syntheses of 4,5,6- and 3,4,5,6-substituted azepanes have been achieved by highly diastereoselective and enantioselective (-)-sparteine-mediated asymmetric lithiation-conjugate additions of N-Boc-N-(p-methoxyphenyl)-2,3-substituted allylamines to a beta-aryl alpha,beta-unsaturated ester followed by hydrolysis, cyclization, and reduction. Access to the enantiomeric adduct is provided by an invertive lithiation-stannylation-lithiation sequence.

SUBMITTER: Lee SJ

PROVIDER: S-EPMC2537463 | biostudies-literature | 2006 Feb

REPOSITORIES: biostudies-literature

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Asymmetric synthesis of 4,5,6- and 3,4,5,6-substituted azepanes by a highly diastereoselective and enantioselective lithiation-conjugate addition sequence.

Lee Suk Joong SJ Beak Peter P

Journal of the American Chemical Society 20060201 7

Asymmetric syntheses of 4,5,6- and 3,4,5,6-substituted azepanes have been achieved by highly diastereoselective and enantioselective (-)-sparteine-mediated asymmetric lithiation-conjugate additions of N-Boc-N-(p-methoxyphenyl)-2,3-substituted allylamines to a beta-aryl alpha,beta-unsaturated ester followed by hydrolysis, cyclization, and reduction. Access to the enantiomeric adduct is provided by an invertive lithiation-stannylation-lithiation sequence. ...[more]

PMID: 16478148

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