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SNAr-Derived Decomposition By-products Involving Pentafluorophenyl Triazolium Carbenes.

ABSTRACT: Pentafluorophenyl triazolium carbenes, widely used in NHC-catalysis, can decompose by several mechanisms. Under high concentration conditions, the azolium may undergo a pentafluorophenyl exchange by a proposed SNAr mechanism to give an inactive salt. In the presence of appropriate substrates, cyclization on the ortho-position of the arene can occur, also by SNAr. These adducts provide a potential pathway for catalyst decomposition and serve as a caveat to the development of new reactions and catalysts.

SUBMITTER: Zhao X

PROVIDER: S-EPMC3873771 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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SNAr-Derived Decomposition By-products Involving Pentafluorophenyl Triazolium Carbenes.

Zhao Xiaodan X Glover Garrett S GS Oberg Kevin M KM Dalton Derek M DM Rovis Tomislav T

Synlett : accounts and rapid communications in synthetic organic chemistry 20130601 10

Pentafluorophenyl triazolium carbenes, widely used in NHC-catalysis, can decompose by several mechanisms. Under high concentration conditions, the azolium may undergo a pentafluorophenyl exchange by a proposed SNAr mechanism to give an inactive salt. In the presence of appropriate substrates, cyclization on the ortho-position of the arene can occur, also by SNAr. These adducts provide a potential pathway for catalyst decomposition and serve as a caveat to the develop ...[more]

PMID: 24379522

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