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Detrifluoroacetylative Generation of Halogenated Enolates: Practical Access to Perhalogenated Ketones and Alkenes.

ABSTRACT: Sequential chlorination/fluorination of aromatic trifluoroacetylated ketones gives 1-aryl 2-chloro-2,4,4,4-tetrafluoro-butan-1,3-dione hydrates that are used for the synthesis of ketones and alkenes exhibiting a terminal bromochlorofluoromethyl group. The hydrates undergo detrifluoroacetylative cleavage and subsequent bromination in the presence of a copper(II)bisoxazoline catalyst, K2CO3 and NBS at room temperature. The corresponding bromochlorofluoromethyl ketones can be applied in Wittig and Horner-Wadsworth-Emmons reactions and dibromoalkenylations.

SUBMITTER: Balaraman K

PROVIDER: S-EPMC5589145 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Detrifluoroacetylative Generation of Halogenated Enolates: Practical Access to Perhalogenated Ketones and Alkenes.

Balaraman Kaluvu K Moskowitz Max M Liu Yang Y Wolf Christian C

Synthesis 20160420 15

Sequential chlorination/fluorination of aromatic trifluoroacetylated ketones gives 1-aryl 2-chloro-2,4,4,4-tetrafluoro-butan-1,3-dione hydrates that are used for the synthesis of ketones and alkenes exhibiting a terminal bromochlorofluoromethyl group. The hydrates undergo detrifluoroacetylative cleavage and subsequent bromination in the presence of a copper(II)bisoxazoline catalyst, K<sub>2</sub>CO<sub>3</sub> and NBS at room temperature. The corresponding bromochlorofluoromethyl ketones can be ...[more]

PMID: 28890578

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