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Synthesis of ?-substituted carbonyl compounds from DMSO-mediated oxidation of enynamides: mechanistic insights and carbon- and hetero-functionalizations.

ABSTRACT: Oxidative coupling of 1,3-enynamides using DMSO as a terminal oxidant has been developed. Carbon as well as unmodified heteroatom nucleophiles, including aliphatic alcohols, thiols, and hydrazides, could be efficiently alkylated at the ?-position in a highly regioselective fashion. The kinetic analysis suggested a nucleophile-dependent mechanism ranging from a concerted SN2'' to a carbocationic mechanism. Thus, the remote site-selectivity was ascribed to the partial positive charge developing at the terminal carbocationic center.

SUBMITTER: Nguyen QH

PROVIDER: S-EPMC6849631 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Synthesis of γ-substituted carbonyl compounds from DMSO-mediated oxidation of enynamides: mechanistic insights and carbon- and hetero-functionalizations.

Nguyen Quynh H QH Nguyen Nguyen H NH Kim Hanbyul H Shin Seunghoon S

Chemical science 20190812 38

Oxidative coupling of 1,3-enynamides using DMSO as a terminal oxidant has been developed. Carbon as well as unmodified heteroatom nucleophiles, including aliphatic alcohols, thiols, and hydrazides, could be efficiently alkylated at the γ-position in a highly regioselective fashion. The kinetic analysis suggested a nucleophile-dependent mechanism ranging from a concerted S<sub>N</sub>2'' to a carbocationic mechanism. Thus, the remote site-selectivity was ascribed to the partial positive charge de ...[more]

PMID: 31803452

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