Chiral Naphthyl-C2-Indole as Scaffold for Phosphine Organocatalysis: Application in Asymmetric Formal [4 + 2] Cycloaddition Reactions
Tingting He, Lei Peng, Shan Li, Fangli Hu, Chuandong Xie, Sheng‐Li Huang, Shiqi Jia, Wenling Qin, Hailong Yan
Abstract
The applications of a newly designed chiral naphthyl-C2-indole bifunctional phosphine organocatalyst in stereoselective formal [4 + 2] cycloaddition reactions were reported. The chiral naphthyl-C2-indole skeleton was introduced to bifunctional phosphine organocatalysis for the first time, and excellent stereocontrol was achieved in two types of formal [4 + 2] cycloaddition reactions. With the optimal catalyst, a series of chiral spirooxindole and hydrodibenzofuran architectures were produced in moderate to good yields with excellent stereoselectivities (up to >99% ee, >20:1 dr).
Topics & Concepts
CycloadditionChemistryOrganocatalysisBifunctionalPhosphineIndole testStereoselectivityEnantioselective synthesisCatalysisCombinatorial chemistrySquaramideOrganic chemistryStereochemistryAxial and Atropisomeric Chirality SynthesisAsymmetric Synthesis and CatalysisMolecular spectroscopy and chirality