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Arylation of gem-difluoroalkenes using a Pd/Cu Co-catalytic system that avoids β-fluoride elimination.

ABSTRACT: Pd^II/Cu^I co-catalyze an arylation reaction of gem-difluoroalkenes using arylsulfonyl chlorides to deliver α,α-difluorobenzyl products. The reaction proceeds through a β,β-difluoroalkyl-Pd intermediate that typically undergoes unimolecular β-F elimination to deliver monofluorinated alkene products in a net C-F functionalization reaction. However to avoid β-F elimination, we offer the β,β-difluoroalkyl-Pd intermediate an alternate low-energy route involving β-H elimination to ultimately deliver difluorinated products in a net arylation/isomerization sequence. Overall, this reaction enables exploration of new reactivities of unstable fluorinated alkyl-metal species, while also providing new opportunities for transforming readily available fluorinated alkenes into more elaborate substructures.

SUBMITTER: Yuan K

PROVIDER: S-EPMC8179108 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Arylation of gem-difluoroalkenes using a Pd/Cu Co-catalytic system that avoids β-fluoride elimination.

Yuan Kedong K Feoktistova Taisiia T Cheong Paul Ha-Yeon PH Altman Ryan A RA

Chemical science 20201125 4

PdII/CuI co-catalyze an arylation reaction of gem-difluoroalkenes using arylsulfonyl chlorides to deliver α,α-difluorobenzyl products. The reaction proceeds through a β,β-difluoroalkyl-Pd intermediate that typically undergoes unimolecular β-F elimination to deliver monofluorinated alkene products in a net C-F functionalization reaction. However to avoid β-F elimination, we offer the β,β-difluoroalkyl-Pd intermediate an alternate low-energy route involving β-H elimina ...[more]

PMID: 34163899

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