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Iridium-Catalyzed Hydrochlorination and Hydrobromination of Alkynes by Shuttle Catalysis.

ABSTRACT: Described herein are two different methods for the synthesis of vinyl halides by a shuttle catalysis based iridium-catalyzed transfer hydrohalogenation of unactivated alkynes. The use of 4-chlorobutan-2-one or tert-butyl halide as donors of hydrogen halides allows this transformation in the absence of corrosive reagents, such as hydrogen halides or acid chlorides, thus largely improving the functional-group tolerance and safety profile of these reactions compared to the state-of-the-art. This method has granted access to alkenyl halide compounds containing acid-sensitive groups, such as tertiary alcohols, silyl ethers, and acetals. The synthetic value of those methodologies has been demonstrated by gram-scale synthesis where low catalyst loading was achieved.

SUBMITTER: Yu P

PROVIDER: S-EPMC7028031 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Iridium-Catalyzed Hydrochlorination and Hydrobromination of Alkynes by Shuttle Catalysis.

Yu Peng P Bismuto Alessandro A Morandi Bill B

Angewandte Chemie (International ed. in English) 20200116 7

Described herein are two different methods for the synthesis of vinyl halides by a shuttle catalysis based iridium-catalyzed transfer hydrohalogenation of unactivated alkynes. The use of 4-chlorobutan-2-one or tert-butyl halide as donors of hydrogen halides allows this transformation in the absence of corrosive reagents, such as hydrogen halides or acid chlorides, thus largely improving the functional-group tolerance and safety profile of these reactions compared to the state-of-the-art. This me ...[more]

PMID: 31769578

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