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Intramolecular Redox-Mannich Reactions: Facile Access to the Tetrahydroprotoberberine Core.

ABSTRACT: Cyclic amines such as pyrrolidine undergo redox-annulations with 2-formylaryl malonates. Concurrent oxidative amine ?-C?H bond functionalization and reductive N-alkylation render this transformation redox-neutral. This redox-Mannich process provides regioisomers of classic Reinhoudt reaction products as an entry to the tetrahydroprotoberberine core, enabling the synthesis of (±)-thalictricavine and its epimer. An unusually mild amine-promoted dealkoxycarbonylation was discovered in the course of these studies.

SUBMITTER: Ma L

PROVIDER: S-EPMC4808586 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Intramolecular Redox-Mannich Reactions: Facile Access to the Tetrahydroprotoberberine Core.

Ma Longle L Seidel Daniel D

Chemistry (Weinheim an der Bergstrasse, Germany) 20150728 37

Cyclic amines such as pyrrolidine undergo redox-annulations with 2-formylaryl malonates. Concurrent oxidative amine α-CH bond functionalization and reductive N-alkylation render this transformation redox-neutral. This redox-Mannich process provides regioisomers of classic Reinhoudt reaction products as an entry to the tetrahydroprotoberberine core, enabling the synthesis of (±)-thalictricavine and its epimer. An unusually mild amine-promoted dealkoxycarbonylation was discovered in the course of ...[more]

PMID: 26220197

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