The incorporation of propane-1,3-diamine into silylant epoxide group through hornogeneous and heterogeneous routes

The polar organic molecule propane-1,3-diamine reacted: (i) with a 3-glycidoxypropyltrimethoxysilane silylant agent, previously anchored on a silica surface in a heterogeneous route to yield the product SiHT or (ii) with the same agent before immobilizing it on the support, in a homogeneous method, to produce a SiHM surface. The epoxy group was opened yielding chelating pendant groups bonded to the inorganic surface. Both products were characterized through elemental analysis, infrared spectroscopy, surface area and thermogravimetry. The ligand concentrations were 0.80 (SiHT) and 1.53 mmol (SiHM), per gram of silica. The heterogeneous route is an easier procedure to produce immobilization. However the homogeneous route provided conditions to obtain a higher density of pendant groups on the surface, which are potentially useful for extracting cations from solutions in an effective way. (C) 2002 Elsevier Science Ltd. All rights reserved.