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Bromine Radical Catalysis by Energy Transfer Photosensitization.

ABSTRACT: We report here a mild, safe, and user-friendly bromine radical catalysis system that enables efficient [3 + 2] cycloaddition of diversely substituted vinyl- and ethynylcyclopropanes with a broad range of alkenes, including drug-like molecules and pharmaceuticals. Key to the success is the use of photosensitizing triplet-state β-fragmentation of a judiciously selected precatalyst, cinnamyl bromide, to generate bromine radicals in a controlled manner using parts per million-level photocatalyst (i.e., 4CzIPN) loading.

SUBMITTER: Chen DF

PROVIDER: S-EPMC8168786 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Bromine Radical Catalysis by Energy Transfer Photosensitization.

Chen Dian-Feng DF Chrisman Cameron H CH Miyake Garret M GM

ACS catalysis 20200130 4

We report here a mild, safe, and user-friendly bromine radical catalysis system that enables efficient [3 + 2] cycloaddition of diversely substituted vinyl- and ethynylcyclopropanes with a broad range of alkenes, including drug-like molecules and pharmaceuticals. Key to the success is the use of photosensitizing triplet-state <i>β</i>-fragmentation of a judiciously selected precatalyst, cinnamyl bromide, to generate bromine radicals in a controlled manner using parts per million-level photocatal ...[more]

PMID: 34079625

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