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C-H functionalization of cyclic amines: redox-annulations with ?,?-unsaturated carbonyl compounds.

ABSTRACT: Cyclic amines such as pyrrolidine and 1,2,3,4-tetrahydroisoquinoline undergo redox-annulations with ?,?-unsaturated aldehydes and ketones. Carboxylic acid promoted generation of a conjugated azomethine ylide is followed by 6?-electrocylization, and, in some cases, tautomerization. The resulting ring-fused pyrrolines are readily oxidized to the corresponding pyrroles or reduced to pyrrolidines.

SUBMITTER: Kang Y

PROVIDER: S-EPMC4477284 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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C-H functionalization of cyclic amines: redox-annulations with α,β-unsaturated carbonyl compounds.

Kang YoungKu Y Richers Matthew T MT Sawicki Conrad H CH Seidel Daniel D

Chemical communications (Cambridge, England) 20150701 53

Cyclic amines such as pyrrolidine and 1,2,3,4-tetrahydroisoquinoline undergo redox-annulations with α,β-unsaturated aldehydes and ketones. Carboxylic acid promoted generation of a conjugated azomethine ylide is followed by 6π-electrocylization, and, in some cases, tautomerization. The resulting ring-fused pyrrolines are readily oxidized to the corresponding pyrroles or reduced to pyrrolidines. ...[more]

PMID: 26051897

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