Applications of Amine-functionalized Mesoporous Silica in Fine Chemical Synthesis

Abstract

SBA-15 silica containing homogeneously distributed amine-functional groups and of fiber or platelet morphology was prepared through a modified co-condensation method using P123 copolymer as template under acidic condition. Synthetic factors which led to wellordered mesoporous materials with high loadings of various amine groups were discussed. The resultant mesoporous materials were efficient base catalysts in Knoevenagel and Claisen-Schmidt addition reactions. The activities over SBA-15 materials with different aminofunctional groups are compared. Moreover, the advantage of ordered large mesopores of SBA-15 in catalyzing liquid phase reactions was demonstrated, and the reaction rate could be further increased when SBA-15 was with platelet morphology and short mesochannels.

Effects of amine structure and base strength on acid–base cooperative aldol condensation

“…However, the discovery rate may be further enhanced by exploiting more rational feedback obtained by means of kinetic modelling in the catalyst design cycle [3][4][5]. base amine sites has a enhancing effect on the catalytic activity of these amines in aldol condensations and other important C C coupling reactions [22][23][24][25][26][27][28][29][30][33][34][35][36][37][38]. Recently it has been demonstrated that an increasing acid strength of the promoting site leads to a decreasing activity which could be explained by a pronounced shift in the equilibrium from the free acid and free base towards the resulting neutralized ion pair [25,26,32].…”

Chitosan as a Sustainable Organocatalyst: A Concise Overview

“…The latter has been extensively developed as a heterogeneous organocatalyst and matrix for the immobilization of transition metals and stabilization of actively growing nanoparticles. [84][85][86] Aminopropyl-tethered silicates exhibit some advantages over chitosan derivatives. For example, they typically possess surface areas (in the order of 500 to 900 m 2 g À1 ) that are up to three times greater than those of chitosan-based aerogels and display uniform pore diameters, which enable them to act as shape-selective molecular sieves (separation of biomolecules) and an ideal confined medium for the uniform growth of nano-objects, including sub-clusters and nanoparticles (nanofabrication and nanochemical synthesis).…”

Ferulic acid functionalized mesoporous silica polymer nanocomposites (SBA/FA) for the adsorption of Cr(VI)

“…Particularly, ordered mesoporous silica materials exhibit remarkable advantages because of their high surface area, large pore volume, tunable pore diameters and flexibility to incorporate different organic-inorganic moieties for various applications in adsorption, ion-exchange and catalysis [1][2][3][4][5][6]. The surface properties can be modified either via co-condensation, in situ or post grafting method [7,8].…”