Highly Enantioselective Control of Dynamic Cascade Transformations by Dual Catalysis: Asymmetric Synthesis of Polysubstituted Spirocyclic Oxindoles

作者：Afewerki Samson; Ma Guangning; Ibrahem Ismail; Liu Leifeng; Sun Junliang; Cordova Armando^*

来源：ACS Catalysis, 2015, 5(2): 1266-1272.

DOI：10.1021/cs501975u

• asymmetric cocatalysis
• alpha,beta-unsaturated aldehydes
• dynamic transformations
• polysubstituted
• spirocyclic oxindoles
• all-carbon quaternary stereocenter

The highly enantioselective (up to >99.5:0.5 er) synthesis of polysubstituted spirocyclic oxindoles with four new contiguous stereocenters, including the spiro all-carbon quaternary center, is disclosed. It is accomplished by the highly stereoselective control of a dynamic conjugate/intramolecular allylic alkylation relay sequence based on the synergistic cooperation of metal and chiral amine catalysts in which the careful selection of organic Nand, metal complex, and chiral amine is essential. The intermolecular C-C bond-forming step occurred only when both the metal and chiral amine catalysts were present.

• 出版日期2015-2