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Dearomatization of aryl sulfoxides: a switch between mono- and dual-difluoroalkylation.

ABSTRACT: Herein we describe the dearomatization of aryl sulfoxides with difluoroenol silyl ether (DFESE) using a rearrangement/addition protocol. The selection of the sulfoxide activator determines whether one or two difluoroalkyl groups are incorporated into dearomatized products. Using TFAA can deliberately halt the reaction at the mono-difluoroalkylated dearomatized intermediate formed via a [3,3]-rearrangement, which can be further trapped by external nucleophiles to give mono-difluoroalkylated alicycles. In contrast, switching to Tf₂O enhances the electrophilicity of dearomatized intermediates, thus allowing for the adoption of a second DFESE to produce dual-difluoroalkylated alicycles.

SUBMITTER: Huang X

PROVIDER: S-EPMC8157523 | biostudies-literature |

REPOSITORIES: biostudies-literature

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