Asymmetric 1,2‐Migration at Vicinal Tetrasubstituted Stereocenters Constructed from α‐Keto Imines

Abstract

AbstractA carbonyl‐assisted asymmetric 1,2‐migratory allylation through in situ generation of vicinal tetrasubstituted stereocenters is reported to access enantiopure α‐amino ketones and amino alcohols with excellent yields and diastereoselectivities. In a remarkable divergence, despite higher steric hindrance, the allylation exclusively occurs on ketones over imines in the first step, followed by a face‐selective 1,2‐allyl transfer, thus highlighting an exciting interplay between two distinct electrophiles. The methodology distinguishes itself through its adaptability to gram‐scale synthesis, showcasing broad functional‐group tolerance and stereodivergence. Density functional theory (DFT) analysis led to a deeper understanding of its selectivity and mechanistic framework. Highlighting its transformative potential, the method was applied to the total synthesis of hapalindole alkaloids.