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Vinylpyridines ammonia

The primary use of a-picoline (2) is as a precursor of 2-vinylpyridine (23). It is also used in a variety of agrochemicals and pharmaceuticals, such as nitrapyrin [1929-82-4] (60) to prevent loss of ammonia from fertilizers picloram [1918-02-1] (61), a herbicide and amproHum [121 -25-5] (62), a coccidiostat. [Pg.335]

As in the synthesis of other bipyridines, several routes to 4,4 -bipyridine have been devised where one of the pyridine rings is built up from simpler components. For example, a dimer of acrolein reacts with ammonia and methanol in the presence of boron phosphate catalyst at 350°C to give a mixture of products including 4,4 -bipyridine (3.4% yield), and in a reaction akin to ones referred to with other bipyridines, 4-vinylpyridine reacts with substituted oxazoles in the presence of acid to give substituted 4,4 -bipyridines. ° ° Condensation of isonicotinaldehyde with acetaldehyde and ammonia at high temperatures in the presence of a catalyst also affords some 4,4 -bipyridine, and related processes give similar results,whereas pyran derivatives can be converted to 4,4 -bipyridine (56% conversion), for example, by reaction with ammonia and air at 350°C with a nickel-alumina catalyst. Likewise, 2,6-diphenyl-4-(4-pyridyl)pyrylium salts afford 2,6-... [Pg.328]

Vinyl groups a or y to the pyridine nitrogen atom readily undergo Michael additions. Water, alcohols, ammonia, amines and hydrogen cyanide are among the nucleophiles which may be added. For example, 2-vinylpyridine and dimethylamine give the adduct (701 X = NMe2). [Pg.265]

One of the most interesting processes in electrically initiated polymerization was an initiation with the solvated electron proposed by Laurin and Parravano (22), who studied electro-anionic polymerization of 4-vinylpyridine in liquid ammonia solution of alkali metal salts in the temperature range — 33 to — 78° C. Rapid and efficient polymerization occurred and conversions of monomer to polymers formed exclusively at the cathode in the form of an orange-red, porous, solid deposit, suggesting the formation of a pile of living polymers. [Pg.388]

Orion model 95-10 ammonia-gas sensing electrode 2.4.1.19 Adsorption onto a vinylpyridine copolymer... [Pg.499]


See other pages where Vinylpyridines ammonia is mentioned: [Pg.318]    [Pg.178]    [Pg.389]    [Pg.95]    [Pg.53]    [Pg.789]    [Pg.202]    [Pg.147]    [Pg.363]   


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Vinylpyridines

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