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Photo-induced catalytic halopyridylation of alkenes

ABSTRACT: The Mizoroki-Heck reaction and its reductive analogue are staples of organic synthesis, but the ensuing products often lack a chemical handle for further transformation. Here we report an atom-economical cross-coupling of halopyridines and unactivated alkenes under photoredox catalysis to afford a series of alkene halopyridylation products. This protocol with mild and redox neutral conditions contributes broad substrate scope. As a complement to conventional Heck-type reaction, this radical process avoids the involvement of β-H elimination and thus useful pyridyl and halide groups could be simultaneously and regioselectively incorporated onto alkenes. The success depends on TFA-promoted domino photocatalytic oxidative quenching activation and radical-polar crossover pathway. Plausible mechanism is proposed based on mechanistic investigations. Moreover, the reserved C − X bonds of these products are beneficial for performing further synthetic elaborations. The Mizoroki–Heck reaction and its reductive analogue are staples of organic synthesis, but the ensuing products often lack a chemical handle for further transformation. Here the authors present a method to add a heterocycle and transformable halide across a double bond via iridium photocatalysis.

SUBMITTER: Guo S

PROVIDER: S-EPMC8586348 | biostudies-literature |

REPOSITORIES: biostudies-literature

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