Quaternized poly-4-vinylpyridine QPVP

Pyridine groups show the nucleophilic catalytic activity. Letsinger and Saveride122 hydrolyzed 2,4-dinitrophenyl-acetate, 72 (DNPA) and 3-nitro-4-acetoxybenzene-sulfonate, 66 (NABS) with partially quaternized poly-4-vinylpyridine (QPVP). 

The polyelectrolyte complex is prepared by mixing poly(sodium styrenesulfonate) (NaSS) and partially quaternized poly(4-vinylpyridine) (QPVP) at [NaSS]/[cationic site of QPVP] = 1.0... 

Recently, the quaternized poly-4-vinylpyridine, 50-54 (QPVP) was found to be an electron acceptor in the charge-transfer interactions 104 Ishiwatari et al.105) studied alkaline hydrolyses of p-nitrophenyl-3-indoleacetate 58 (p-NPIA) and N-(indole-3-acryloyl) imidazole 59 (IAI) (electron donor) in the presence of QPVP. The fcobs vs. polyelectrolyte concentration plots are shown in Fig. 12. As is seen in... 

Izumrudov et al.145) reported non-equimolar water-soluble polyelectrolyte complexes composed of PMAA and quaternized poly(4-vinylpyridine) (poly(N-ethyl-4-vinylpyridinium bromide) QPVP). When the pH is increased after making the mixing ratio (expressed as the molar ratio of [QPVP]/ [PMAA]) equal to unity in the neutralization (a) of PMAA beyond a = 0.8, it is confirmed that an equimolar water-insoluble complex is formed. If the initial... 

Cordes et al995 carried out alkaline hydrolyses of p-nitrophenylhexanoate 55 (PNPH) in the presence of poly-4-vinylpyridine partially quaternized with dodecyl-bromide and ethylbromide (QPVP). They also found that the polyelectrolytes are increasingly effective as catalysts with an increasing ratio of dodecyl to ethyl groups, and the hydrophobic interactions are important in determining the catalytic efficiency. They observed the inhibitory effects of several gegen-anions fluoride ions are the weakest inhibitor, and nitrate is the strongest (F- < Cl < S04 [Pg.159]

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