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Scope and Limitations of Xanthate-Mediated Synthesis of Functional ?-Thiolactones.

ABSTRACT: A modular platform based on free-radical xanthate addition to alkenes enables access to a large series of functional ?-thiolactones. This methodology includes two different pathways based on xanthate chemistry involving radical addition and Chugaev elimination steps. The first method uses the addition of an ester-functionalized xanthate to various commercially functional alkenes, whereas the second one is based on the addition of functional xanthates to an ester-functionalized alkene. In both cases, a series of xanthate/alkene monoadducts was obtained, and their thermolysis and subsequent cyclization led to a library of functional ?-thiolactones in moderate to good yield. For a few cases where it may not be possible to directly incorporate some targeted functional groups via the proposed process involving free radicals and high temperature, a bromo-functionalized thiolactone was used as a starting material for chemical transformations.

SUBMITTER: Langlais M

PROVIDER: S-EPMC6644131 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Scope and Limitations of Xanthate-Mediated Synthesis of Functional γ-Thiolactones.

Langlais Marvin M Coutelier Olivier O Destarac Mathias M

ACS omega 20181219 12

A modular platform based on free-radical xanthate addition to alkenes enables access to a large series of functional γ-thiolactones. This methodology includes two different pathways based on xanthate chemistry involving radical addition and Chugaev elimination steps. The first method uses the addition of an ester-functionalized xanthate to various commercially functional alkenes, whereas the second one is based on the addition of functional xanthates to an ester-functionalized alkene. In both ca ...[more]

PMID: 31458371

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