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Divergent Regioselectivity in Photoredox-Catalyzed Hydrofunctionalization Reactions of Unsaturated Amides and Thioamides.

ABSTRACT: A direct method to construct 2-oxazolines and 2-thiazolines from corresponding allylic amides and thioamides is reported. The redox-neutral intramolecular hydrofunctionalization is enabled by a dual catalyst system comprised of the 9-mesityl-N-methyl acridinium tetrafluoroborate and phenyl disulphide and exhibits complete selectivity for the anti-Markovnikov regioisomeric products. The cyclization of allylic thioamides is postulated to operate via a modified mechanism in which oxidation of the thioamide, rather than the alkene, is responsible for the observed reactivity.

SUBMITTER: Morse PD

PROVIDER: S-EPMC4273915 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Divergent Regioselectivity in Photoredox-Catalyzed Hydrofunctionalization Reactions of Unsaturated Amides and Thioamides.

Morse Peter D PD Nicewicz David A DA

Chemical science 20150101 1

A direct method to construct 2-oxazolines and 2-thiazolines from corresponding allylic amides and thioamides is reported. The redox-neutral intramolecular hydrofunctionalization is enabled by a dual catalyst system comprised of the 9-mesityl-<i>N</i>-methyl acridinium tetrafluoroborate and phenyl disulphide and exhibits complete selectivity for the <i>anti</i>-Markovnikov regioisomeric products. The cyclization of allylic thioamides is postulated to operate via a modified mechanism in which oxid ...[more]

PMID: 25541590

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