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Y-Picoline

The -picoline in the base recovered from the residual picoline - ZnCl, complexes is separated from the y-picoline by fractional freezing pure /8-picoline has m.p. —18 -2° and y-picoline has m.p. -f 3 -6°. [Pg.179]

If much liquid ammonia is lost during the preparation of the sodamide, the volume should be m e up to 500-600 ml. before adding the y picoline. [Pg.846]

Important commercial alkylpyridine compounds are a-picoline (2), Ppicoline (3), y-picoline (4), 2,6-lutidine (5), 3,5-lutidine (6), 5-ethyl-2-methylpyridine (7), and 2,4,6-coUidine (8). In general, the alkylpyridines serve as precursors of many other substituted pyridines used in commerce. These further substituted pyridine compounds derived from alkylpyridines are in turn often used as intermediates in the manufacture of commercially usehil final products. [Pg.321]

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. [Pg.326]

Fig. 1. Four-bond reactions formaldehyde, acetaldehyde, and ammonia mainly give pyridine (1), and acetaldehyde and ammonia give a- (2) and y-picoline... Fig. 1. Four-bond reactions formaldehyde, acetaldehyde, and ammonia mainly give pyridine (1), and acetaldehyde and ammonia give a- (2) and y-picoline...
The vapoi-phase analogue of this hquid-phase reaction (eq. 22) is used to make a- (2) and y-picoline (4) (eq. 23). The gas-phase products ate... [Pg.332]

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. [Pg.336]

The separation of mixtures involving N-methyl-JLtetrahydropyridines into their pure components by means of gas-liquid chromatography was discussed in a report by Holik et al. (87). They found that, using tris(/3-cyanoethoxymethyl)-y-picoline as the stationary phase, the primary factors involved in the specific retention volumes of these enamines is the electronic effect of a methyl substituent and the nitrogen atom on the carbon-carbon double bond. It was observed that 1,3-dimethyl-Zl -tetrahydropyridine (141) has a smaller specific retention volume and, hence, is eluted before... [Pg.50]

High yields and stable products result when R = i-Bu and R = Me2N, i-BuO or i-Bu or if R and R are (Me3Si)2CH If substituents with lower electron-releasing capacity are used, the method fails because of disproportionation into AIR 3 + Al. Addition of y-picoline (y-pic) to Al2(i-Bu)4 gives " Al2(i-Bu)4(y-pic)2 with enhanced stability of the metal-metal bond. The action of B2H(j on Al2(i-Bu)4 produces Al2(BH2)4 in which both Al—Al and Al — B bonds occur ". ... [Pg.36]

Y Picoline. Commercially pure y-picoline contains )S-picoline and 2 6-lutidine and sometimes traces of non-basic impurities (aromatic hydrocarbons) which cannot be separated by fractionation. The non-basic impurities are removed by steam distillation of the base in dilute hydrochloric or sulphuric acid solution (for details, see under a Picoline). The impure y-picoline is converted into the zinc chloride complexes of the component bases the 2 6-lutidine - ZnClj complex is the least stable and upon steam distillation of the mixture of addition compounds suspended in water, 2 6-lutidine passes over flrst. The complete separation of the 2 6-lutidine may be detected by a determination of the density and the refractive index of the dry recovered base at varioiu stages of the steam distillation. The physical properties are —... [Pg.178]

Blanco et al. (1994) reported measurements of the vapor pressure (P,at) for p-xylene, y-picoline, piperidine, pyridine and tetralin. The data for piperidine and pyridine are given in Table 3.4. A suitable equation to correlate these data is Antoine s relationship given next... [Pg.46]

When N-ethylated-a-picoline, y-picoline, and lepidine were reacted with the ethoxy cation 75, instead of the expected cyanines of type 136 or 137 the products were dicationic species, whose structures were assigned to be bis(diphenylcyclopropenium)-monomethine cyanines, e.g. 142105 ... [Pg.29]

Methyl phenyl ether, m55 Methyl phenyl ketone, a31 2-Methyl-2-phenylpropane, b523 Methyl y-picolinate, m413... [Pg.275]

Besides uracil-6-iminophosphorane, the iminophosphorane component was extended to pyrazole 3 and pyrazolon-4-iminophosphoranes 363 (94JOC3985). In its electron distribution, 363 can be compared with uracil 346. With arylisocyanates, pyridine, or y-picoline, zwitterionic pyrazolo [3, 4 4,5]pyrido[6,l-a]pyrimidines (364) are obtained and with isoquinoline, 365 is formed (Scheme 131). Again, both systems show a typical negative solvatochromism (94JOC3985). [Pg.236]

An interesting rearrangement is involved in the reaction between N-hydroxy-iV JV" diphenylguanidine (225), toluenesulfonyl chloride, and y-picoline in benzene at 0°. This yields a colorless toluenesulfonate which with alkali gives red anhydro-s-triazolo[4,3-a]pyridinium hydroxide (226), which is a derivative of meso-ionic l,2,4-triazol-3-imine (216). ... [Pg.47]

Problem 20.30 Account for the fact that the CH/s of a- and -y-picolines (methylpyridines) are more acidic than the CH, of toluene. <... [Pg.466]

Problem 20.31 Give the products formed when y-picoline reacts with C HjLi and then with (a) CO, then H,0 (6) C H,CHO then H,0. ... [Pg.466]

In pyridine derivatives, a- and y-picolines readily lose a proton from the methyl group. It is easy to fmd parallel reactivity in the picolines and the nitrotoluenes N=CHN02. Further development of the reactivity patterns includes a methano-lytic study of several trichloromethylpyridines [29],... [Pg.89]


See other pages where Y-Picoline is mentioned: [Pg.313]    [Pg.177]    [Pg.178]    [Pg.178]    [Pg.178]    [Pg.179]    [Pg.662]    [Pg.846]    [Pg.848]    [Pg.280]    [Pg.280]    [Pg.183]    [Pg.149]    [Pg.244]    [Pg.37]    [Pg.178]    [Pg.178]    [Pg.179]    [Pg.662]    [Pg.846]    [Pg.848]    [Pg.144]    [Pg.220]    [Pg.150]    [Pg.262]    [Pg.104]    [Pg.512]    [Pg.464]   
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See also in sourсe #XX -- [ Pg.4 , Pg.1213 ]

See also in sourсe #XX -- [ Pg.394 , Pg.409 ]

See also in sourсe #XX -- [ Pg.343 ]

See also in sourсe #XX -- [ Pg.200 ]




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