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Quaternary Onium Salts Immobilized on Inorganic Matrices
Author(s) -
Tundo Pietro,
Venturello Paolo,
Angeletti Enrico
Publication year - 1985
Publication title -
israel journal of chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.908
H-Index - 54
eISSN - 1869-5868
pISSN - 0021-2148
DOI - 10.1002/ijch.198500108
Subject(s) - onium , chemistry , catalysis , reagent , solvent , ionic liquid , aqueous solution , selectivity , inorganic chemistry , organic chemistry , polymer chemistry , ion
Onium salts immobilized on silica gel and alumina show unusual properties because of the presence of the polar inorganic support. Under liquid—liquid phase‐transfer catalysis conditions these systems can also catalyze reactions carried out without stirring, and unlike the corresponding onium salts supported on polystyrenic matrix, they do not need the use of polar solvent. Moreover, different matrices with different geometries in the micropores are differently functionalized and may induce selectivity towards reagents with different molecular size. The polar and hydrophilic matrix strongly affects the affinities of the immobilized onium salts in the anion exchange process, producing a higher affinity towards hydrophilic inorganic and lipophilic organic anions, with respect to that observed for the homogeneous and polystyrene supported onium salts. In aqueous solution the onium salts supported on inorganic matrices are able to adsorb the reactants and to vary the reaction microenvironment as the micellar catalysts do.