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Alkyl Radical Addition to Aliphatic and Aromatic N-Acylhydrazones Using an Organic Photoredox Catalyst.

ABSTRACT: Increased versatility of intermolecular radical addition to imino acceptors via photoredox catalysis is reported. Primary and secondary radicals, generated via visible-light photocatalysis from alkyl biscatecholatosilicates with organocatalyst 4CzIPN, add successfully to both aromatic and aliphatic N-acylhydrazones in the presence of MgCl2. With N-benzoylhydrazones, a simple reductive cleavage of the N-N bond of the hydrazine adduct furnishes the free amine. Synthetic utility is exemplified in a synthetic application toward repaglinide, a clinically important hypoglycemic agent.

SUBMITTER: Cullen STJ

PROVIDER: S-EPMC6900872 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Alkyl Radical Addition to Aliphatic and Aromatic N-Acylhydrazones Using an Organic Photoredox Catalyst.

Cullen Stephen T J STJ Friestad Gregory K GK

Organic letters 20190927 20

Increased versatility of intermolecular radical addition to imino acceptors via photoredox catalysis is reported. Primary and secondary radicals, generated via visible-light photocatalysis from alkyl biscatecholatosilicates with organocatalyst 4CzIPN, add successfully to both aromatic and aliphatic N-acylhydrazones in the presence of MgCl2. With N-benzoylhydrazones, a simple reductive cleavage of the N-N bond of the hydrazine adduct furnishes the free amine. Synthetic ut ...[more]

PMID: 31560554

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