Homogenous formation and quaternization of urea-functionalized imidazolyl silane and its immobilization on silica for surface-confined ionic liquid stationary phases

Abstract

A novel facile and efficient immobilization strategy was introduced on the basis of the reaction between isocyanate and amine and applied in surface modification of mesoporous silica spheres with a series of urea-functionalized imidazolium salts bearing aliphatic chains of different lengths and a large aromatic group. This resulted in an array of multifunctional silica materials as HPLC stationary phases with selectivity significantly influenced by the substituents and functional groups.