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Synthesis of ?-halo-?,?-difluoromethyl ketones by a trifluoroacetate release/halogenation protocol.

ABSTRACT: Three series of ?-halo-?,?-difluoromethyl ketones are prepared from highly ?-fluorinated gem-diols by exploiting the facile release of trifluoroacetate, followed by immediate trapping of the liberated ?,?-difluoroenolate with an electrophilic chlorine, bromine, or iodine source. The products are typically isolated in good yields, even in the case of sensitive, ?-iodo-?,?-difluoromethyl ketones. Also, we demonstrate that an ?-iodo-?,?-difluoromethyl ketone will participate in a copper-promoted reaction to forge a new carbon-carbon bond.

SUBMITTER: John JP

PROVIDER: S-EPMC3227119 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

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Synthesis of α-halo-α,α-difluoromethyl ketones by a trifluoroacetate release/halogenation protocol.

John Jinu P JP Colby David A DA

The Journal of organic chemistry 20111013 21

Three series of α-halo-α,α-difluoromethyl ketones are prepared from highly α-fluorinated gem-diols by exploiting the facile release of trifluoroacetate, followed by immediate trapping of the liberated α,α-difluoroenolate with an electrophilic chlorine, bromine, or iodine source. The products are typically isolated in good yields, even in the case of sensitive, α-iodo-α,α-difluoromethyl ketones. Also, we demonstrate that an α-iodo-α,α-difluoromethyl ketone will participate in a copper-promoted re ...[more]

PMID: 21995668

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