A Michael addition initiated cyclopropanation/[1,5]-hydrogen shift has been developed for the enantioselective synthesis of Rauhut–Currier products. The reaction of α-alkyl diazoesters and in situ generated o-quinone methides proceeds in the presence of chiral oxazaborolidinium ion, providing Z-stereocontrolled Rauhut–Currier products in high yields (up to 96%) with excellent Z/E selectivities (>20:1)
Catalytic Asymmetric Formal C–C Bond Insertion Reaction of Aldehydes via 1,2-Acyl Shift: Construction of All-Carbon Quaternary Stereocenters with Three Carbonyl Groups
作者:Hye-Min Jeong、Jin Won Lee、Dong Kyu Kim、Do Hyun Ryu
DOI:10.1021/acscatal.3c04726
日期:2024.1.5
The formal C–H bond insertionreaction into aldehydes via 1,2-hydride shift has been well established; however, the formal C–C bond insertion is more challenging. In the presence of chiral oxazaborolidinium ion (COBI) catalyst, the formal C–C bond insertion into glyoxals was developed via an 1,2-acyl shift for the construction of α-alkyl-α-formyl-β-ketoesters in high yield (up to 97%) with high enantioselectivity