Chloromethyl resin

NaHC03 (0.2 g) was added to a suspension of chloromethylated polystyrene-1 % divinylbenzene copolymer (Merrifield resin, 0.5 g, 0.76 mmol/g) in DMSO (3 mL). After stirring for 7 h at 155 °C, the resin was washed successively with H20, MeOH, DMF, CH2C12, and Et20 and then dried under reduced pressure. To confirm the conversion of the chloromethyl resin into the aldehyde resin, two analyses were used FTIR analysis showing the typical carbonyl absorption at 1700.5 cm-1 and microanalysis showing the absence of any chlorine on the resin. The benzaldehyde resin (1.0g, 0.59mmol/g) was suspended in... 

Subramanian and coworkers developed polymeric sorbents using different support materials (such as Merrifield chloromethylated resin, Amberlite XAD 16) and complexing ligands (amides, phosphonic acids, TTA), and evaluated their binding affinity for U(VI) over other diverse ions, even under high acidities. The practical utility of these sorbents was demonstrated using simulated waste solutions (220-222). Shamsipur et al. reported the solid-phase extraction of ultra trace U(VI) in natural waters using octadecyl silica membrane disks modified by TOPO (223). The method was found satisfactory for the extraction and determination of uranium from different water samples. 

The weak-base anion-exchange resins, that is, the secondary RCH2NHR and tertiary amine RCH2NR2, are produced by reacting the chloromethylated resin with lower substituted amines or with ammonia [124],... 

The chloromethylated resin can now be combined with many different nucleophiles, Amines give basic ion-exchange resins while Ph2P-Li gives a phosphine suitable for complexation to transition metals. 

Alternatively, we prefer to prepare polymers containing the thiol functionally (15,25) by reacting chloromethylated resin with thiourea (25). The reaction of y-CI Cl with thiourea gives a supported isothiouromium chloride. The latter solid is reacted with hydroxyl groups to produce a thiol-containing polymer. 

Hydroxymethyl dihydropyran was coupled to chloromethyl resin via an ether linkage to yield 41 (Scheme 21) [45]. The alcohol was then attached as a THP ether (42). After combinatorial synthesis, the alcohol was released under acidic conditions. 

Immobilization of glyoxylate represents a versatile means of gaining access to many biologically relevant compounds. Thus, reaction of potassium monoethyl tartrate with chloromethylated resin and subsequent oxidative cleavage of the resulting supported tartrate (549) with H5IO6 smoothly afforded the polymer-supported glyoxylate 550 in its hydrated form [397] (Scheme 113). 

Preparation of Polymer Catalysts (I-VI). Crosslinked polystyrene beads with 1% divinylbenzene mesh size 200-400 (SXl) purchased from Bio-Rad Laboratories, Inc., were chloromethylated by the method of Pepper, Paisley, and Young(24). The resin contained 4.59 meq/g of chloromethyl groups according to the modified Volhard method.(25) The chloromethylated resin was allowed to swell in dioxane-ethanol and reacted with histamine pyridine or triethylamine was used as an acid captor. The reaction mixture... 

In two closely related papers [40, 41] CP/MAS was used to examine a series of styrene-divinylbenzene (St-DVB) and chloromethylated resins. In the first part of this study the authors were concerned with trying to determine the residual amount of unreacted vinyl groups present in St-DVB resins (see Section 3). In order to increase the sensitivity of the method the authors used C -labelled divinylbenzene (labelled in the methine position) and combined this with unlabelled styrene (1-20% by weight). The final resins were examined by CP/MAS and it was found that even for a very lightly erosslinked... 

Simple hydroxylic resins were obtained from chloromethylated resins (1), commercially available (gel-type resins) or prepared by chloromethylation of styrene units according to the method described by Itsuno (in particular for macroreticular polymers) [5]. Chloromethyl groups were reacted with acetic acid and EtsN to give polymeric esters 2 which were hydrolyzed with KOH-H20-methylglycol [6]. Quantitative transformation of chloromethyl into hydroxymethyl groups was observed in all cases. 

Polymer bound 1,4-diols (23) were obtained by reaction of alcoxylates derived from mono-O-benzylated tartaric acid derivatives (22) and chloromethylated resins and then modification of the resulting polymers. Treatment with TiX4 species gave Ti catalysts 24 (Scheme 6). 

Kirschning and coworkers have recently reported the synthesis of a resin-bound diketone for the sequestration of amines and hydrazines [14]. The resin-bound diketone was synthesized via oxidation of a chloromethyl resin, followed by reductive coupling with 2,4-pentadione, to provide the requisite scavenger resin. This resin was found to be more efficient than supported-aldehydes for amine and hydrazine scavenging and, furthermore, found to be selective for the scavenging of primary amines over secondary amines (Scheme 8.10). 

Stir 5 g chloromethyl resin (1.0 mmol Cl/g) in 40 mL CCI4 for 10 min. Add 165 mg iodine and a solution of 8 mL bromine in 17 mL CCI4 and stir the mixture for 20 h at 24°C in the dark. Filter the resin wash with 150 mL each of dioxane, water, 1 M NaHCOs, water, A/A-dimethylformamide (DMF), methanol, and DCM and dry. The resin weight gain should be -65%. The theoretical weight gain for monobromination of all aromatic rings is 71%. 

Cover chloromethyl resin (0.5 to 1 mmol Cl/g resin 1 equivalent Cl) and potassium acetate (10 equiv.) with methyl cellosolve (approximately 6 mL/... 

Treat 10 g (7.3 mmol) chloromethyl resin suspended in 70 mL DMF with 1.64 g (10 mmol) 4-(p-hydroxyphenyl)-2-butanone in the presence of 0.54 g (10 mmol) sodium methoxide at 85°C for 24 h. Filter the dark brownish reaction mixture and wash the resin with DMF, DCM, and methanol to yield... 

Chloromethyl resin Wang resin 2-Chlorotrityl resin Rink amide resin Kaiser oxime resin TentaGel S RAM... 

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