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Direct Zinc(II)-Catalyzed Enantioconvergent Additions of Terminal Alkynes to ?-Keto Esters.

ABSTRACT: The addition of terminal alkynes to racemic ?-stereogenic ?-keto esters was achieved in high levels of stereoselectivity, affording versatile tertiary propargylic alcohols containing two stereocenters. This environmentally benign enantioconvergent reaction proceeds with perfect atom economy, requires no solvent, and is catalyzed by a non-toxic zinc salt. The alkyne moiety can be leveraged in downstream transformations including hydrogenation to the corresponding saturated tertiary alcohol, which represents the product of a formal enantioconvergent aliphatic nucleophile addition.

SUBMITTER: Zavesky BP

PROVIDER: S-EPMC5554871 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Direct Zinc(II)-Catalyzed Enantioconvergent Additions of Terminal Alkynes to α-Keto Esters.

Zavesky Blane P BP Johnson Jeffrey S JS

Angewandte Chemie (International ed. in English) 20170620 30

The addition of terminal alkynes to racemic β-stereogenic α-keto esters was achieved in high levels of stereoselectivity, affording versatile tertiary propargylic alcohols containing two stereocenters. This environmentally benign enantioconvergent reaction proceeds with perfect atom economy, requires no solvent, and is catalyzed by a non-toxic zinc salt. The alkyne moiety can be leveraged in downstream transformations including hydrogenation to the corresponding saturated tertiary alcohol, which ...[more]

PMID: 28557339

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