Preparation of A Novel Chiral Ligand Exchange Chromatographic Stationary Phase by Click Chemistry

Click chemistry was applied to immobilize L-prolinamide derivative onto azide-modified silica gel to prepare a novel chiral stationary phase for ligand exchange chromatography (Click-CSP). Azide functionalities were introduced onto the silica gel by reacting gamma-chloropropyltriethoxysilane with silica gel, and then the obtained product was reacted with sodium azide. The azide-modified silica gel reacted with N-propargyl prolinamide chiral selector prepared in methanol at room temperature for 48 h in the presence of copper(I) bromide to give a novel chiral stationary phase for ligand exchange chromatography. The developed protocol combines the benefits of operational simplicity, exceptionally mild conditions and high surface loadings up to 0.47 mmol/g. The enantiomeric separation of some D, L-amino acids were achieved on the synthesized chiral ligand exchange chromatographic stationary phase using 0.2 mmol/L Cu(Ac)(2) solution as mobile phase at column temperature of 40 degrees C with selectivity factors alpha from 1. 14 to 2. 42. The chromatographic resolutions of some D,L-amino acids and the stability of the Click-CSP firmly illustrate the potential of click chemistry for preparation chiral stationary phase for ligand exchange chromatography.