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Evidence for in situ catalyst modification during the Pd-catalyzed conversion of aryl triflates to aryl fluorides.

ABSTRACT: A mechanistic investigation of the Pd-catalyzed conversion of aryl triflates to fluorides is presented. Studies reveal that C-F reductive elimination from a LPd(II)(aryl)F complex (L = t-BuBrettPhos or RockPhos) does not occur when the aryl group is electron rich. Evidence is presented that a modified phosphine, generated in situ, serves as the actual supporting ligand during catalysis with such substrates. A preliminary study of the reactivity of a LPd(II)(aryl)F complex based on this modified ligand is reported.

SUBMITTER: Maimone TJ

PROVIDER: S-EPMC3354724 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

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Evidence for in situ catalyst modification during the Pd-catalyzed conversion of aryl triflates to aryl fluorides.

Maimone Thomas J TJ Milner Phillip J PJ Kinzel Tom T Zhang Yong Y Takase Michael K MK Buchwald Stephen L SL

Journal of the American Chemical Society 20111021 45

A mechanistic investigation of the Pd-catalyzed conversion of aryl triflates to fluorides is presented. Studies reveal that C-F reductive elimination from a LPd(II)(aryl)F complex (L = t-BuBrettPhos or RockPhos) does not occur when the aryl group is electron rich. Evidence is presented that a modified phosphine, generated in situ, serves as the actual supporting ligand during catalysis with such substrates. A preliminary study of the reactivity of a LPd(II)(aryl)F complex based on this modified ...[more]

PMID: 21999801

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