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A Visible Light-Driven Minisci-Type Reaction with N-Hydroxyphthalimide Esters.

ABSTRACT: A visible light-promoted protocol for the redox-neutral coupling of N-hydroxyphthalimide esters with different N-heterocyclic compounds is described. The reaction proceeds through an alkyl radical intermediate generated by reductive decarboxylation of N-hydroxyphthalimide esters. In contrast to the original Minisci protocol, polyalkylation can largely be avoided. Mechanistic investigations revealed a radical chain mechanism which in some cases can proceed even if no photocatalyst is added. This valuable and functional group-tolerant reaction produces substituted heterocycles in moderate to excellent yield. The use of inexpensive starting materials and LEDs as the light source are key features of this C-C bond formation.

SUBMITTER: Kammer LM

PROVIDER: S-EPMC6017455 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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A Visible Light-Driven Minisci-Type Reaction with N-Hydroxyphthalimide Esters.

Kammer Lisa Marie LM Rahman Aliyaah A Opatz Till T

Molecules (Basel, Switzerland) 20180327 4

A visible light-promoted protocol for the redox-neutral coupling of N-hydroxyphthalimide esters with different N-heterocyclic compounds is described. The reaction proceeds through an alkyl radical intermediate generated by reductive decarboxylation of N-hydroxyphthalimide esters. In contrast to the original Minisci protocol, polyalkylation can largely be avoided. Mechanistic investigations revealed a radical chain mechanism which in some cases can proceed even if no photocat ...[more]

PMID: 29584642

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