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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 |

REPOSITORIES: biostudies-literature

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