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Alkynylation of Thiols with Ethynylbenziodoxolone (EBX) Reagents: ?- or ?- ?-Addition?

ABSTRACT: The alkynylation of thiols with EthynylBenziodoXolone (EBX) reagents is a fast and chemoselective method for the synthesis of thioalkynes. Combined experimental and computational studies are reported, which led to the identification of a new mechanism for this reaction, proceeding via an initial sulfur-iodine interaction followed by ?-addition, ?-elimination, and a 1,2-shift. Depending on the substituent on the alkyne, this mechanism can be favored over the previously disclosed concerted ?-addition pathway.

SUBMITTER: Wodrich MD

PROVIDER: S-EPMC4700532 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Alkynylation of Thiols with Ethynylbenziodoxolone (EBX) Reagents: α- or β- π-Addition?

Wodrich Matthew D MD Caramenti Paola P Waser Jerome J

Organic letters 20151214 1

The alkynylation of thiols with EthynylBenziodoXolone (EBX) reagents is a fast and chemoselective method for the synthesis of thioalkynes. Combined experimental and computational studies are reported, which led to the identification of a new mechanism for this reaction, proceeding via an initial sulfur-iodine interaction followed by β-addition, α-elimination, and a 1,2-shift. Depending on the substituent on the alkyne, this mechanism can be favored over the previously disclosed concerted α-addit ...[more]

PMID: 26652212

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