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Divergent 1,2-carboallylation of terminal alkynes enabled by metallaphotoredox catalysis with switchable triplet energy transfer.

ABSTRACT: We report a metallaphotoredox strategy for stereodivergent three-component carboallylation of terminal alkynes with allylic carbonates and alkyl trifluoroborates. This redox-neutral dual catalytic protocol utilizes commercially available organic photocatalyst 4CzIPN and nickel catalysts to trigger a radical addition/alkenyl-allyl coupling sequence, enabling straightforward access to functionalized 1,4-dienes in a highly chemo-, regio-selective, and stereodivergent fashion. This reaction features a broad substrate generality and a tunable triplet energy transfer control with pyrene as a simple triplet energy modulator, offering a facile synthesis of complex trans- and cis-selective skipped dienes with the same set of readily available substrates.

SUBMITTER: Qin J

PROVIDER: S-EPMC10631246 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature

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Divergent 1,2-carboallylation of terminal alkynes enabled by metallaphotoredox catalysis with switchable triplet energy transfer.

Qin Jian J Zhang Zhuzhu Z Lu Yi Y Zhu Shengqing S Chu Lingling L

Chemical science 20231013 43

We report a metallaphotoredox strategy for stereodivergent three-component carboallylation of terminal alkynes with allylic carbonates and alkyl trifluoroborates. This redox-neutral dual catalytic protocol utilizes commercially available organic photocatalyst 4CzIPN and nickel catalysts to trigger a radical addition/alkenyl-allyl coupling sequence, enabling straightforward access to functionalized 1,4-dienes in a highly chemo-, regio-selective, and stereodivergent fashion. This reaction features ...[more]

PMID: 37969584

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