2- Vinylpyridine

2-Vinylpyridine. In a very similar way 2-vinyl pyridine has proved to be an interesting monomer. Whereas for the Cs+ ion pairs of the growing carboanion is 

Lochmann, M. Rodova, J. Petranek, and P. Lim, J. Polymer Set., Polymer Chem., 

The influence of the penultimate group of a growing chain is not limited, however, to the case of these polar monomers, but has been shown to arise in styrene polymerizations in cyclohexane and more recently in styrene copolymerizations with l,l-diphenylethylene. ° Thus in reactions of 1,1-diphenylalkyl-lithium compounds, these alkyls with aromatic substituents representing effectively a styryl penultimate group react approximately an order of magnitude more slowly than a species with an unsubstituted alkyl chain, while at the same time the latter ion pair is less dissociated. This has been interpreted in terms of a through space interaction between the penultimate group and the terminal one (19). Partial 

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Indoles can also be alkylated by conjugate addition under alkaline conditions. Under acidic conditions, alkylation normally occurs at C3 (see Section 11.1). Table 9.1 includes examples of alkylation by ethyl acrylate, acrylonitrile, acrylamide and 4-vinylpyridine. 

Strauss and Williamst have studied coil dimensions of derivatives of poly(4-vinylpyridine) by light-scattering and viscosity measurements. The derivatives studied were poly(pyridinium) ions quaternized y% with n-dodecyl groups and (1 - y)% with ethyl groups. Experimental coil dimensions extrapolated to 0 conditions and expressed relative to the length of a freely rotating repeat unit are presented here for the molecules in two different environments ... 

A number of methods such as ultrasonics (137), radiation (138), and chemical techniques (139—141), including the use of polymer radicals, polymer ions, and organometaUic initiators, have been used to prepare acrylonitrile block copolymers (142). Block comonomers include styrene, methyl acrylate, methyl methacrylate, vinyl chloride, vinyl acetate, 4-vinylpyridine, acryUc acid, and -butyl isocyanate. 

An industrially important example is the condensation of a- (2) or y-picoline (4) with aqueous formaldehyde to form the corresponding ethanolpyridines, 2-ethanolpyridine [104-74-2] (22) and 4-ethanolpyridine [5344-27-4] respectively, followed by dehydration of the alcohols to give 2- (23) or 4-vinylpyridine. 

Shipment Methods and Packaging. Pyridine (1) and pyridine compounds can be shipped in bulk containers such as tank cars, rail cars, and super-sacks, or in smaller containers like fiber or steel dmms. The appropriate U.S. Department of Transportation (DOT) requirements for labeling are given in Table 4. Certain temperature-sensitive pyridines, such as 2-vinylpyridine (23) and 4-vinylpyridine are shipped cold (<—10°C) to inhibit polymerisation. Piperidine (18) and certain piperidine salts are regulated within the United States by the Dmg Enforcement Agency (DEA) (77). Pyridines subject to facile oxidation, like those containing aldehyde and carbinol functionaUty, can be shipped under an inert atmosphere. 

The main use of y-picoline (4) is in the production of the antituberculosis agent, isonia2id (31). Compound (4) is also used to make 4-vinylpyridine, and subsequendy polymers. 

The Time-Zero film process has an efficient receiving layer consisting of a graft copolymer of 4-vinylpyridine and a vinylhenzyltrimethylammonium salt grafted to hydroxyethylceUulose (81,82). The accuracy of color rendition was improved in the Time-Zero SX-70 film by the use of the xanthene magenta dye-developer (1). 

The other main source of various pyridopyridazines from pyridines are the [4 + 2] cycloaddition reactions, already mentioned (Section 2.15.8.3), between vinylpyridines and azodicarboxylic esters (79T2027, 79KGS639) or triazolidinediones e.g. 78KGS651). 2-Vinyl-pyridines gave reduced pyrido[3,2-c]pyridazines (370), 4-vinylpyridines gave [3,4-c] analogues, whilst 2-methyl-5-vinylpyridine furnishes a mixture of the [2,3-c] and [4,3-c] compounds. Yields are low, however, and these remain curiosities for practical synthetic purposes. 

Indazole adds to acrylonitrile and 4-vinylpyridine giving 1- or 2-substituted derivatives depending on the 7-substituents (69BSF2064). It also reacts with epoxystyrene to form (259). 

Poly(4-vinylpyridine) [25232-41-1] M (105.1)n. Purified by repeated pptn from solns in EtOH and dioxane, and then EtOH and ethyl acetate. Finally, freeze-dried from rcrt-butanol. 

The Zincke reaction has also been adapted for the solid phase. Dupas et al. prepared NADH-model precursors 58, immobilized on silica, by reaction of bound amino functions 57 with Zincke salt 8 (Scheme 8.4.19) for subsequent reduction to the 1,4-dihydropyridines with sodium dithionite. Earlier, Ise and co-workers utilized the Zincke reaction to prepare catalytic polyelectrolytes, starting from poly(4-vinylpyridine). Formation of Zincke salts at pyridine positions within the polymer was achieved by reaction with 2,4-dinitrochlorobenzene, and these sites were then functionalized with various amines. The resulting polymers showed catalytic activity in ester hydrolysis. ... 

Reaction of 9-bromo-2-morphohno-4//-pyrido[l, 2-n]pyrimidin-4-ones with 4-vinylpyridine in DMF at 80 °C for 16 h in the presence of CS2CO3 and PdCbCdppf), and with amines and phenols in boiling THF for 20 h in the presence of KOr-Bu and PdCbCdppf) yielded 9-[2-(4-pyridyl)vinyl), 9-(substituted amino), and 9-aryloxy derivatives, respectively (01MIP9). 4-Hydroxyaniline gave a 9-(4-hydroxyphenyl)amino derivative. 

The polymers were prepared using MAA as functional monomer and EDMA as crosslinking monomer if not otherwise noted. VPY= 2- or 4-vinylpyridine TRIM = trimethylolpropane trimethacrylate DPGE = (R)-N,0-dimethacryloylphenylglycinol PYAA = 3-(4-pyridinyl)acrylic acid. 

Considering functional group complementarity, other commodity monomers may also be used. Thus for templates containing acid groups, basic functional monomers are preferably chosen. The 2- or 4-vinylpyridines (VPY) are particularly well-suited for the imprinting of carboxylic acid templates and provide selectivities of the same... 

Pyridinium ylide is considered to be the adduct car-bene to the lone pair of nitrogen in pyridine. The validity of this assumption was confirmed by Tozume et al. [12J. They obtained pyridinium bis-(methoxycarbonyl) meth-ylide by the photolysis of dimethyl diazomalonate in pyridine. Matsuyama et al. [13] reported that the pyridinium ylide was produced quantitatively by the transylidalion of sulfonium ylide with pyridine in the presence of some sulfides. However, in their method it was not easy to separate the end products. Kondo and his coworkers [14] noticed that this disadvantage was overcome by the use of carbon disulfide as a catalyst. Therefore, they used this reaction to prepare poly[4-vinylpyridinium bis-(methoxycarbonyl) methylide (Scheme 12) by stirring a solution of poly(4-vinylpyridine), methylphenylsulfo-nium bis-(methoxycarbonyl)methylide, and carbon disulfide in chloroform for 2 days at room temperature. 

On the other hand, poly(ethoxycarbonylimino-4-vi-nylpyridinium ylide) (Scheme 13) was prepared essentially by the same method from 1-ethoxycarbonylimino-pyridinium ylide, as described by Hafner [15] from the reaction of poly (4-vinylpyridine) with nitrene, generated from the pyrolysis of ethyl azidoformate. 

In contrast to /3-PCPY, ICPY did not initiate copolymerization of MMA with styrene [39] and AN with styrene [40]. However, it accelerated radical polymerization by increasing the rate of initiation in the former case and decreasing the rate of termination in the latter case. The studies on photocopolymerization of MMA with styrene in the presence of ICPY has also been reported [41], /8-PCPY also initiated radical copolymerization of 4-vinylpyridine with methyl methacrylate [42]. However, the ylide retarded the polymerization of N-vinylpyrrolidone, initiated by AIBN at 60°C in benzene [44]. (See also Table 2.)... 

The structures of these ylide polymers were determined and confirmed by IR and NMR spectra. These were the first stable sulfonium ylide polymers reported in the literature. They are very important for such industrial uses as ion-exchange resins, polymer supports, peptide synthesis, polymeric reagent, and polyelectrolytes. Also in 1977, Hass and Moreau [60] found that when poly(4-vinylpyridine) was quaternized with bromomalonamide, two polymeric quaternary salts resulted. These polyelectrolyte products were subjected to thermal decyana-tion at 7200°C to give isocyanic acid or its isomer, cyanic acid. The addition of base to the solution of polyelectro-lyte in water gave a yellow polymeric ylide. 

Nucleic acids are anionic under the neutral conditions. Thus, the syntheses of model compounds of the opposite charge are interesting for the discussion of electrostatic contributions in specific interactions of nucleic acids. We have tried to synthesize cationic models by the Menschutkin reaction of poly-4-vinylpyridine with 9-(2-chlo-roethyl)adenine, l-(2-chloroethyl)thymine, and 7-(2-chloroethyl)theophylline15,16 The obtained polymers are poly l-[2-(adenin-9-yl)ethyl]-4-pyridinioethylene chloride 7(APVP), poly l-[2-(thymin-l-yl)ethyl]-4-pyridinioethylene chloride 8 (TPVP), and poly l-[2-(theophyllin-7-yl)ethyl]-4-pyridiniothylene chloride 9 (THPVP), respectively. 

UPEI), and poly[l-(uridin-5 -yl)-iminoethylene halide], 13 (UPEI ). They were obtained by quaternization of poly-4-vinylpyridine or polyethylenimine with ehlo-roethylated, ehloropropylated, or ehlorated nucleic acid bases. 

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]

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... 

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). 

Kabanov et al.131) found that a copolymer of 4-vinylpyridine and acroleinoxime, 82 (PPox), is a powerful catalyst for the hydrolyses of PNPA, NABA, and 3-nitro-4-trimethyl-acetoxybenzoic acid 83 (NTBA). The activity of the copolymer was 103 times higher than that of the low-molecular-weight oxime, iso-butyraldoxime. They proposed the cooperative activation of the oxime- and pyridine-groups in the vicinity of pyridinium cation groups of the copolymer. 

We discussed more quantitatively the correlation of the adsorption with catalytic activity in the heterogeneous systems using poly(4-vinylpyridine-co-divinylbenzene) quaternized with alkylhalide [e. g. 88 (RC16PVP)] as a catalyst and p-nitrophenyl-valerate (PNPV) as a substrate147. ... 

Vinylaromatics 2 (or 4) vinylpyridine Isopropenylpyridines" Isopropeny lquin o leine"... 

A great variety of suitable polymers is accessible by polymerization of vinylic monomers, or by reaction of alcohols or amines with functionalized polymers such as chloromethylat polystyrene or methacryloylchloride. The functionality in the polymer may also a ligand which can bind transition metal complexes. Examples are poly-4-vinylpyridine and triphenylphosphine modified polymers. In all cases of reactively functionalized polymers, the loading with redox active species may also occur after film formation on the electrode surface but it was recognized that such a procedure may lead to inhomogeneous distribution of redox centers in the film... 

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