Work

Development of a Copper‐Free Click Reaction for Asymmetric Rh Diene Catalysis Under Confinement

Year: 2025

Type: article

Abstract: We report a copper‐free alkynone‐amine click reaction as a versatile strategy for the immobilization of chiral norbornadiene‐based ligands. This methodology was applied to both soluble amines and amino‐functionalized mesoporous silica support materials. Therefore, a series of ( E )‐ and ( Z )‐configured enaminones were synthesized, revealing a strong substituent‐dependent stereoselectivity: primary amines exclusively formed ( Z )‐enaminones, while secondary amines afforded ( E )‐isomers with high selectivity (>99:1). The resulting enaminone‐functionalized diene ligands were subsequently applied in Rh catalysis both under homogeneous and heterogeneous conditions. Regarding the enantioselectivity it was found that the catalysts performed well under homogeneous conditions for 1,2‐additions while heterogeneous conditions gave the best results for the Rh‐catalyzed isoxazole ring contraction.

Source: Advanced Synthesis & Catalysis

DOI: 10.1002/adsc.70213