Organocatalytic Enantioselective Michael-Michael-Michael-Aldol Condensation Reactions: Control of Six Stereocenters in a Quadruple-Cascade Asymmetric Synthesis of Polysubstituted Spirocyclic Oxindoles

Prakash D Chaudhari; Bor-Cherng Hong; Gene-Hsiang Lee

doi:10.1021/acs.orglett.7b02962

Organocatalytic Enantioselective Michael-Michael-Michael-Aldol Condensation Reactions: Control of Six Stereocenters in a Quadruple-Cascade Asymmetric Synthesis of Polysubstituted Spirocyclic Oxindoles

Org Lett. 2017 Nov 17;19(22):6112-6115. doi: 10.1021/acs.orglett.7b02962. Epub 2017 Nov 1.

Authors

Prakash D Chaudhari¹, Bor-Cherng Hong¹, Gene-Hsiang Lee²

Affiliations

¹ Department of Chemistry and Biochemistry, National Chung Cheng University , Chia-Yi, 621, Taiwan, R.O.C.
² Instrumentation Center, National Taiwan University , Taipei, 106, Taiwan, R.O.C.

PMID: 29090937
DOI: 10.1021/acs.orglett.7b02962

Abstract

An organocatalyzed enantioselective Michael-Michael-Michael-aldol cascade reaction for the construction of cyclopentane fused spirooxindoles was achieved. The domino reaction provided the spirooxindoles with six contiguous stereocenters including a quaternary center in good yields (55-64%) with excellent enantioselectivities (up to >99% ee). Enantioselective Michael-Michael-Michael-aldol condensation-aromatization reactions of an isomeric product were observed.

Publication types

Research Support, Non-U.S. Gov't