Polystyrene, chloromethylated amine reactions

Strong base anion exchange resins are manufactured by chloromethylation of sulphonated polystyrene followed by reaction with a tertiary amine ... 

Polymers with pendant carbodiimide groups 27 are also synthesized from crossUnked polystyrene. In this synthetic route crossUnked polystyrene beads are chloromethylated and converted to the amines. Reaction with isopropyl isocyanate gives the corresponding ureas, which are treated with tosyl chloride and triethylamine to produce the crossUnked polycarbodiimides. This polymer is used in the polymer supported Moffatt oxidation of alcohols into aldehydes or ketones using benzene/DMSO. ... 

Chloromethylation of polystyrene followed by reaction with a tertiary amine. 

Although phase transfer agents have been attached to clays, silica and alumina, the vast majority of studies have used organic polymers, especially polystyrene, as the support. The earliest of these triphase catalysts was prepared from 12% chloromethylated polystyrene crosslinked with 2% divinylbenzene by reaction with a tertiary amine. A wide range of triphase catalysts has since been reported, some examples of which are shown in Figure 5.16. 

The direct quaternization of chloromethylated polystyrenes by tertiary amines or phosphines represents the easiest way to obtain polymer-supported quaternary onium salt (12,13). A lipophilic character of quaternary cation and a topology allowing sufficient cation-anion separation also play an important role (35,36). A linear spacer chain (of about 10 carbon atoms) between the catalytic site and the polymer backbone substantially increases the reaction rates. The loading of quaternary onium groups also affects catalytic efficiency, the influence being different for directly bonded and spaced groups, e.g. 10 and 11, respectively (37). 

Aromatic electrophilic substitution is used commercially to produce styrene polymers with ion-exchange properties by the incorporation of sulfonic acid or quaternary ammonium groups [Brydson, 1999 Lucas et al., 1980 Miller et al., 1963]. Crosslinked styrene-divinyl-benzene copolymers are used as the starting polymer to obtain insoluble final products, usually in the form of beads and also membranes. The use of polystyrene itself would yield soluble ion-exchange products. An anion-exchange product is obtained by chloromethylation followed by reaction with a tertiary amine (Eq. 9-38) while sulfonation yields a cation-exchange product (Eq. 9-39) ... 

A homogeneous anion-exchange membrane can be obtained by introducing a quaternary amine group into polystyrene by a chloromethylation procedure followed by an amination with a tertiary amine according to the following reaction scheme ... 

Polymer-bound rhodium clusters were used for catalytic hydrogenations of a,/3-unsaturated aldehydes to allylic alcohols. Amination of chloromethylated polystyrene with 2-(2-(dimethylamino)ethoxy)ethanol gave an amine-functionalized polymer. Using the aminated polystyrene and Rh6(CO)i6 in the presence of H2 and CO or CO and water, various a,/ -unsaturated aldehydes were chemoselectively hydrogenated to give allylic alcohols in high yields, generally >95% conversion and 80-100% selectivity, at 303 K. Under the reaction conditions, a number of anionic clusters form, which can be recovered as ions paired to the ammonium cations of the polymer. Clusters identified by... 

HN J From chloromethyl polystyrene by treatment with tris(2-ami noethyl )amine in DMF. Ti Scavengers to remove excesses of isocyanates, carboxylic acid chlorides or sulfonyl chlorides from reaction mixtures. - - ... 

Reaction of Chloromethylated Polystyrene with a Tertiary Amine. 403... 

Amine complexes. The effect of immobilization of the Cu(II) complexes of polymeric amines has been examined and reviewed by Challa et al. ( ). The polymeric ligands were varied by using the following species polymer-bound dimethylbenzylamlne (formed by treatment of chloromethylated polystyrene with dimethylamlne), the copolymer of styrene and 4-vinyl-pyridine and the copolymer of styrene and N-vinylimidazole. The reaction examined was the Cu(II) oxidative dimerization of 2,6-disubstituted phenols (Equation 1). 

The kinetics of amination of chloromethylated polystyrene with monohydroxydialkyl tertiary amines show that the reactions proceed in two steps, at two different rates. The rate changes take place at conversions of45-50%. These rates are favorably influenced by increases in the dielectric constants of the solvents. Two different rate constants also exist in reactions with 3-alkylamino-propionitiile. 

The kinetics of amination of chloromethylated polystyrene with monohydroxy dialkyl tertiary amines shows that the reactions proceed in two steps, at two different rates. The rate changes take... 

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