Application of Phase-Transfer Catalysis to the Chemical Modification of Cross-Linked Polystyrene Resins

The application of phase-transfer catalysis to the introduction of new functionalities in several cross-linked polystyrene resins was studied. In general, the three-phase reactions gave excellent results and high functional yields. Nucleophilic displacements on chloromethylpolystyrene were used to prepare resins containing acetyl, hvdroxymethyl, cyanomethyl, dinitrile, mononitrile monoester, diester, thiol, and various other functionalities. Addition of cyanide ion to a polystyrylcarboxaldehyde resin produced cyanohydrins which could be trapped by reaction with acetic anhydride or a reactive halide. Other phase-transfer reactions involving the use of thiol, hydroxyl or cyanomethyl resins as nucleophiles were also studied. Reactions involving symmetrical difunctional molecules occurred mostly at one extremity only, indicating that in these phase-transfer reactions site-site interactions can be limited.