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Efficient Access to Multifunctional Trifluoromethyl Alcohols through Base-Free Catalytic Asymmetric C-C Bond Formation with Terminal Ynamides.

ABSTRACT: The asymmetric addition of terminal ynamides to trifluoromethyl ketones with a readily available chiral zinc catalyst gives CF3 -substituted tertiary propargylic alcohols in up to 99?% yield and 96?%?ee. The exclusion of organozinc additives and base as well as the general synthetic utility of the products are key features of this reaction. The value of the ?-hydroxy-?-trifluoromethyl ynamides is exemplified by selective transformations to chiral Z- and E-enamides, an amide, and N,O-ketene acetals. The highly regioselective hydration, stereoselective reduction, and hydroacyloxylation reactions proceed with high yields and without erosion of the ee?value of the parent ?-hydroxy ynamides.

SUBMITTER: Cook AM

PROVIDER: S-EPMC4806781 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Efficient Access to Multifunctional Trifluoromethyl Alcohols through Base-Free Catalytic Asymmetric C-C Bond Formation with Terminal Ynamides.

Cook Andrea M AM Wolf Christian C

Angewandte Chemie (International ed. in English) 20160125 8

The asymmetric addition of terminal ynamides to trifluoromethyl ketones with a readily available chiral zinc catalyst gives CF3 -substituted tertiary propargylic alcohols in up to 99 % yield and 96 % ee. The exclusion of organozinc additives and base as well as the general synthetic utility of the products are key features of this reaction. The value of the β-hydroxy-β-trifluoromethyl ynamides is exemplified by selective transformations to chiral Z- and E-enamides, an amide, and N,O-ketene aceta ...[more]

PMID: 26806871

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