SOLID-SOLID-LIQUID PHASE-TRANSFER REACTIONS CATALYZED BY POLYMER-SUPPORTED UREAS

Polymer-supported ureas were prepared by copolymerization of the corresponding vinyl monomers and divinylbenzene with 2,2'-azoisobutyronitrile. These polymers show catalytic activity in the reaction of 1-bromooctane with solid potassium thiocyanate, although the corresponding monomeric ureas are inactive. The catalytic activity is enhanced remarkably by replacing the amino hydrogen for a methyl group. Further, the catalytic activity is affected by some experimental parameters such as stirring, particle size of the catalyst, degree of crosslinking, and solvent. On the basis of the above results, a plausible catalytic reaction mechanism consisting of collisional contact between the solid catalyst and the reagent is proposed.