Asymmetric Catalytic Synthesis of Hexahydropyrrolo‐isoquinolines via Three‐Component 1,3‐Dipolar‐Cycloaddition
Zhaojing Li, Nian Xu, Ning Guo, Yuqiao Zhou, Lili Lin, Xiaoming Feng
Abstract
Abstract An asymmetric three‐component 1,3‐dipolar cycloaddition of 3,4‐dihydroisoquinolines, bromoacetates and α,β‐unsaturated pyrazole amide is realized by using a chiral N,N’ ‐dioxide‐Y(OTf) 3 complex as the catalyst. The process includes a base‐promoted formation of dihydroisoquinolium ylides in situ, and a chiral Lewis acid‐catalyzed asymmetric [3+2] cycloaddition with α,β‐unsaturated pyrazole amides. A series of hexahydropyrrolo‐isoquinolines are obtained in moderate to good yields with excellent diastereo‐ and enantioselectivities.
Topics & Concepts
CycloadditionCatalysisChemistryPyrazoleAmideComponent (thermodynamics)1,3-Dipolar cycloadditionLewis acids and basesMedicinal chemistryOrganic chemistryPhysicsThermodynamicsCyclopropane Reaction MechanismsOxidative Organic Chemistry ReactionsSynthesis and Catalytic Reactions