Collective Syntheses of 8-Oxoprotoberberines via Sequential In(OTf)<sub>3</sub>-Catalyzed Cyclization and Pd(OAc)<sub>2</sub>-Catalyzed Heck Coupling
Zenghui Sun, Xinhang Zhang, Jiayue Fu, Lianjie Zhang, Maosheng Cheng, Lu Yang, Yongxiang Liu
Abstract
Six 8-oxoprotoberberines were synthesized collectively in four steps with acceptable yields (14–19%), of which the products 8-oxopalmatine, 8-oxopseudopalmatine, 8-oxoberberine, and 8-oxopseudoberberine come from nature. The synthetic route was featured with the In(OTf) 3 -catalyzed cyclization and Heck coupling. Moreover, the syntheses of the natural products berberine, canadine, and iambertine were achieved via various reductions from 8-oxoberberine, which provided a concise approach to the syntheses of this kind of alkaloids.
Topics & Concepts
ChemistryHeck reactionCatalysisCombinatorial chemistryCoupling (piping)PalladiumStereochemistryOrganic chemistryEngineeringMechanical engineeringBerberine and alkaloids researchAlkaloids: synthesis and pharmacologyTraditional and Medicinal Uses of Annonaceae