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Rapid access to t-butylalkylated olefins enabled by Ni-catalyzed intermolecular regio- and trans-selective cross-electrophile t-butylalkylation of alkynes.

ABSTRACT: Among the carbo-difunctionalization of alkynes, the stereoselective dialkylation of alkynes is the most challenging transformation due to associated competitive side reactions and thus remains underdeveloped. Herein, we report the first Ni-catalyzed regio- and trans-selective cross-dialkylation of alkynes with two distinct alkyl bromides to afford olefins with two aliphatic substituents. The reductive conditions circumvent the use of organometallic reagents, enabling the cross-dialkylation process to occur at room temperature from two different alkyl bromides. This operationally simple protocol provides a straightforward and practical access to a wide range of stereodefined dialkylated olefins with broad functional group tolerance from easily available starting materials.

SUBMITTER: Zhan YZ

PROVIDER: S-EPMC9068203 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Rapid access to t-butylalkylated olefins enabled by Ni-catalyzed intermolecular regio- and trans-selective cross-electrophile t-butylalkylation of alkynes.

Zhan Yi-Zhou YZ Meng Huan H Shu Wei W

Chemical science 20220330 17

Among the carbo-difunctionalization of alkynes, the stereoselective dialkylation of alkynes is the most challenging transformation due to associated competitive side reactions and thus remains underdeveloped. Herein, we report the first Ni-catalyzed regio- and trans-selective cross-dialkylation of alkynes with two distinct alkyl bromides to afford olefins with two aliphatic substituents. The reductive conditions circumvent the use of organometallic reagents, enabling the cross-dialkylatio ...[more]

PMID: 35655892

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