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The Eschenmoser coupling reaction under continuous-flow conditions.

ABSTRACT: The Eschenmoser coupling is a useful carbon-carbon bond forming reaction which has been used in various different synthesis strategies. The reaction proceeds smoothly if S-alkylated ternary thioamides or thiolactames are used. In the case of S-alkylated secondary thioamides or thiolactames, the Eschenmoser coupling needs prolonged reaction times and elevated temperatures to deliver valuable yields. We have used a flow chemistry system to promote the Eschenmoser coupling under enhanced reaction conditions in order to convert the demanding precursors such as S-alkylated secondary thioamides and thiolactames in an efficient way. Under pressurized reaction conditions at about 220 °C, the desired Eschenmoser coupling products were obtained within 70 s residence time. The reaction kinetics was investigated and 15 examples of different building block combinations are given.

SUBMITTER: Singh S

PROVIDER: S-EPMC3170046 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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The Eschenmoser coupling reaction under continuous-flow conditions.

Singh Sukhdeep S Köhler J Michael JM Schober Andreas A Groß G Alexander GA

Beilstein journal of organic chemistry 20110825

The Eschenmoser coupling is a useful carbon-carbon bond forming reaction which has been used in various different synthesis strategies. The reaction proceeds smoothly if S-alkylated ternary thioamides or thiolactames are used. In the case of S-alkylated secondary thioamides or thiolactames, the Eschenmoser coupling needs prolonged reaction times and elevated temperatures to deliver valuable yields. We have used a flow chemistry system to promote the Eschenmoser coupling under enhanced reaction c ...[more]

PMID: 21915222

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