B(C6F5)3-catalyzed stepwise 1,5-hydride migration/cyclization: diastereoselective construction of carbocyclic β-amino acid derivatives†
Abstract
Concerted 1,5-hydride migration/cyclization reactions represent an efficient approach for the construction of six-membered cyclic scaffolds. However, their applications are severely restricted by the requirement of strongly electron-withdrawing functional groups, expanding conjugation and branched substituents. Herein, a stepwise 1,5-hydride migration/cyclization reaction enabled by B(C6F5)3 is established, where the above limitations could be overcome. The substrate scope is considerably expanded, and a series of amine-tethered simple aliphatic α,β-unsaturated acid derivatives are well compatible, delivering the corresponding six-membered carbocyclic β-amino acid derivatives with complete diastereoselectivity.