Poly hydrolysis with esterification

A similar method of hydrolysis was described for poly( vinyl alcohol) used as a template. In this case, T was -CH2-CH- and, after hydrolysis, poly(vinyl alcohol) and polyacrylic or polymethacrylic acid were obtained. The hydrolyzed product gives the color reaction with I2 in the presence of H3BO3 - specific to poly(vinyl alcohol). The second product of hydrolysis, after esterification by diazomethane, was identified as polyfmethyl methacrylate) by NMR and IR spectrometry. Hydrolysis was also applied in the case of ladder-type polymers obtained by polymerization of mutliallyl monomers. The polymerization should result in polymer consisting, at least partly, ladder-type blocks ... 

Diastereoselective [2+2] photocycloaddition of a polymer-supported cyclic chiral enone with ethylene has been reported (Scheme 12.33) [43]. The auxiliary was derived from (-)-8-(p-methoxyphenyl) menthol (87). Protection of the secondary alcohol and demethylation were carried out to give (-)-8-(p-hydroxyphenyl)menthyl acetate (88). An alkyl linker was introduced and finally loaded to poly (ethylene glycol) grafted Wang resin. Deprotection of the alcohol functionality was followed by esterification with cyclohexen-3-one-l-carboxylic acid to provide the chiral enone 89. The photochemical reaction with ethylene was performed by irradiating with light (k > 280 nm). Trifluoroacetic acid (TFA) or aqueous hydrolysis with... 

After hydrolysis by 2N methanol solution of H2SO4, the product was neutralized with KOH to pH=5 and methanol evaporated. The dry residue was expected to be poly(allilamine), polymethacrylic acid, and K2SO4. Indeed, after extraction with anhydrous methanol and acetone, poly(allilamine) was identified by NMR and IR spectrometries. After evaporation, solvent from the methanol part of the extract insoluble in chloroform part was obtained. After esterification by diazomethane the product was identified as polyfmethyl methacrylate) on the basis of IR and H-NMR spectroscopy. IR spectroscopy was applied in order to examine the copolymerization of multimethacrylate (p-cresyl-formaldehyde oligomers with methacrylic groups) with st3rrene. It was found that double bond peak at 1650 cm disappeared during the process and it was absent in the product of polymerization. Polymerization and... 

Moreover, lipase-catalyzed reactions of linear and cyclic poly(3-hydroxy-butanoates) were subjected to hydrolysis, transesterification, and intramolecular esterification. A cyclic polymer along with linear polymers was pro-... 

Acyl chloride-functionalized SWCNTs are also susceptible to reactions with other nucleophiles, e.g. alcohols. Haddorfs group reported the preparation of soluble ester-functionalized carbon nanotubes SWCNT-COO(CH2)17CH3 (Fig. 1.6a) obtained by esterification with octadecanol [134]. The syntheses of soluble polymer-bound and dendritic ester-functionalized SWCNTs have been reported by Riggs et al. by attaching poly(vinyl acetate-co-vinyl alcohol) (Fig. 1.6b) [135] and hydrophilic and lipophilic dendron-type benzyl alcohols [119], respectively, to SWCNT-COC1 (Fig. 1.6c). These functional groups could be removed under basic and acidic hydrolysis conditions and thus additional evidence for the nature of the attachment was provided [119, 136]. 

Neenan and Miller [118] reported the preparation of poly (arylester) dendrons using a convergent iterative sequence consisting of esterification and hydrolysis reactions as illustrated in Scheme 14. The key intermediate in the synthesis of these dendrons is 5-(te/V-butyldimethylsiloxy)isophthaloyl dichloride, 48, which is first converted to the diester with phenol, followed by hydrolysis to the diester phenol. This dendron is designated [3-OH] indicating it contains three phenyl... 

On the other hand, we reexamined in detail the ring size of the cyclic structural units of poly-AA s by means of IR, 1H-NMR, and C-NMR spectroscopy these analytical procedures were applied to the structural analysis of poly-AA, the poly(acrylic acid) derived from hydrolysis of the poly-AA, and the poly(methyl acrylate) obtained by subsequent esterification of the poly(acryl-ic acid) in comparison with the corresponding model polymers of five- or six-membered ring structure. Then, we investigated in detail the effects of polymerization conditions on the ring size of poly-AA s, i.e., on the intramolecular addition modes in the cyclopolymerization of AA since five- or six-membered ring anhydride structure can be formed via intramolecular hh or ht addition of the uncyclized radical to the internal double bond(22,23). 

Further development of the SLM-ionic liquid methodology has been coupled with lipase-catalyzed esterification and ester-hydrolysis reactions in the feed gas (interface 1) and receiving phase (interface 2), respectively, to facilitate selective transport of various organic acids with aryl groups (via their esters) from aqueous solutions by utilizing different substrate specificity of lipases in a SLM system (Fig. 5.6-11) [118]. In the enzymatic SLM systems a poly(propene) membrane with water-immiscible [RMIM][X] (R = butyl, hexyl, octyl and X = [PFe]" and [(CF3S02)2N] ) ionic liquid phases were used. 

For the preparation of synthetic hydroxy polymers, hydroxyl groups can be introduced by copolymerization of the base monomer with a hydroxy monomer. These groups can then be used for esterification or etherification (Jarowenko, 1965), but the relatively high cost of hydroxy monomers detracts from the widespread use of direct copolymerization. Instead, one introduces the groups required by the complete or partial hydrolysis of the ester groups in an appropriately hydrolyzable polymer, such as poly(vinyl acetate). Complete hydrolysis yields poly(vinyl alcohol) (PVA), a water-soluble polymer with considerable utility as a stabilizer and viscosity modifier for aqueous systems ... 

In order to exploit the inductive effect of the amide bond on the hydrolysis of the ester linkage in the polymer backbone the amide and ester linkage should be ideally separated by one methylene unit. It was apparent that a hydroxyacetamide structure would yield such an linkage. Hydroxyacetamide amidediols were obtained in high yields as the thermodynamically favorable product upon heating glycolic acid with alkane diamine neat with removal of w ater (Barrows, 1982, 1988, 1994). The polymer is then obtained either by trans esterification polymerization of the diol (bis-hydroxyacetamides) with the desired diester of the diacid or by the reaction of bis-hydroxyacetamides with diacid chlorides (Scheme 3) (Barrows 1982, 1988, 1994). Poly (ester-amides) can be prepared from a wide variety of different bis-hydrox acetamide amidediols and diacids. 

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