2,4 Hexadienoic acid

CARBOXYLICACIDS-SURVEY] (Vol 5) trans,trans-2,4-Hexadienoic acid [110-44-1]... [Pg.474]

An excess of crotonaldehyde or aUphatic, ahcyhc, and aromatic hydrocarbons and their derivatives is used as a solvent to produce compounds of molecular weights of 1000—5000 (25—28). After removal of unreacted components and solvent, the adduct referred to as polyester is decomposed in acidic media or by pyrolysis (29—36). Proper operation of acidic decomposition can give high yields of pure /n j ,/n7 j -2,4-hexadienoic acid, whereas the pyrolysis gives a mixture of isomers that must be converted to the pure trans,trans form. The thermal decomposition is carried out in the presence of alkaU or amine catalysts. A simultaneous codistillation of the sorbic acid as it forms and the component used as the solvent can simplify the process scheme. The catalyst remains in the reaction batch. Suitable solvents and entraining agents include most inert Hquids that bod at 200—300°C, eg, aUphatic hydrocarbons. When the polyester is spHt thermally at 170—180°C and the sorbic acid is distilled direcdy with the solvent, production and purification can be combined in a single step. The solvent can be reused after removal of the sorbic acid (34). The isomeric mixture can be converted to the thermodynamically more stable trans,trans form in the presence of iodine, alkaU, or sulfuric or hydrochloric acid (37,38). [Pg.283]

Hexadienoic acid, 2385 Hexamethylenetetramine, 2477 Magnesium, 4690 Magnesium-nickel hydride, 4464 Paraformaldehyde, 0417 Poly(ethylene), 0782... [Pg.136]

For a decade or so [CoH(CN)5] was another acclaimed catalyst for the selective hydrogenation of dienes to monoenes [2] and due to the exclusive solubility of this cobalt complex in water the studies were made either in biphasic systems or in homogeneous aqueous solutions using water soluble substrates, such as salts of sorbic add (2,4-hexadienoic acid). In the late nineteen-sixties olefin-metal and alkyl-metal complexes were observed in hydrogenation and hydration reactions of olefins and acetylenes with simple Rii(III)- and Ru(II)-chloride salts in aqueous hydrochloric acid [3,4]. No significance, however, was attributed to the water-solubility of these catalysts, and a new impetus had to come to trigger research specifically into water soluble organometallic catalysts. [Pg.10]

For some monomers (e.g., nitroethylene and 2-cyano-2,4-hexadienoic acid ester, CH3-CH=CH-CH=C(CN)-COOR), anionic polymerization can be conducted in aqueous alkaline solution. Other anionic initiators are Lewis bases, e.g., tertiary amines or phosphines, and organometallic compounds (see Sect. 3.2.1.2). Since the polarizability of unsaturated compounds depends very much on the substituents and on the solvent used, there are considerable differences in the effectiveness of the initiators mentioned. [Pg.192]

Synonyms potassium 2, 4—hexadienoate sorbic acid potassium salt 2, 4— hexadienoic acid potassium salt. [Pg.774]

Hexadienoic acid hexadienic acid (2-butenylidene) acetic acid 2-pro-penylacrylic acid Solid White 112.14... [Pg.576]

Hexadienoic acid potassium salt sorbic acid potassium salt potassium 2,4-hexadi-enonate... [Pg.1060]

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