Butyrate oxidation

Other workers have demonstrated the specificity of antagonisms among the fluoro acids. Kalnitsky and Barron found the inhibition of butyrate oxidation to be more profound with fluorobutyrate than with fluoroacetate. Kandel and Chenoweth could prevent or reverse the toxic manifestations of fluoro-acetate with glyceryl monoacetate and those of fluorobutyrate with glyceryl monobutyrate in vivo, but they could not demonstrate cross protections with these compounds. 

At the first Symposium on Phosphorous Metabolism, held in Baltimore in the spring of 1951, Barker reviewed the results of studies with enzyme preparations of C. kluyveri as well as complimentary studies in the field of CoA metabolism. Based on a most remarkable critical analysis of the available information, he proposed a mechanism for the oxidation of butyrate by soluble extracts of C. kluyveri (see Fig. 1) in which CoA derivatives of 4-carbon compounds at various states of oxidation were postulated as the active intermediates, and in which cleavage of acetoacetyl CoA to form two equivalents of acetyl-CoA) [the reverse of reaction (26)] was the final step. The observed stoichiometry of one mole each of acetyl-P and acetate as ultimate products of butyrate oxidation [reaction (3)] was explained by the obligatory coupling of butyrate oxidation with reaction (25), needed to regenerate free CoA, and with reaction (27), in which butyryl-CoA is formed. 

It is noteworthy that when Barker first proposed this scheme of fatty acid oxidation, there was only inferential evidence for a role of CoA in butyrate oxidation in C. kluyveri, and there was no evidence of any kind to implicate CoA in the oxidation of fatty acids by animal enzyme systems. In fact it was not until one year later that a soluble system capable of oxidizing fatty acids in the presence of added CoA was prepared from animal tissues. It is therefore a tribute to Barker s imagination and conceptual analysis that within a few years after his report, his hypothesis was shown to be correct in every significant detail, not only in C. kluyveri but in higher animals as well.J... 

The mechanisms of butyrate oxidation in C. kluyveri and in animals differ significantly... 

Although turnover of the catalyst is low, even unreactive cyclohexane[526] and its derivatives are oxidatively carbonylated to cyclohexanecarboxylic acid using KiS Og as a reoxidant in 565% yield based on Pd(II)[527]. Similarly, methane and propane are converted into acetic acid in 1520% yield based on Pd(II) and butyric acid in 5500% yield [528],... 

Butane-Naphtha Catalytic Liquid-Phase Oxidation. Direct Hquid-phase oxidation ofbutane and/or naphtha [8030-30-6] was once the most favored worldwide route to acetic acid because of the low cost of these hydrocarbons. Butane [106-97-8] in the presence of metallic ions, eg, cobalt, chromium, or manganese, undergoes simple air oxidation in acetic acid solvent (48). The peroxidic intermediates are decomposed by high temperature, by mechanical agitation, and by action of the metallic catalysts, to form acetic acid and a comparatively small suite of other compounds (49). Ethyl acetate and butanone are produced, and the process can be altered to provide larger quantities of these valuable materials. Ethanol is thought to be an important intermediate (50) acetone forms through a minor pathway from isobutane present in the hydrocarbon feed. Formic acid, propionic acid, and minor quantities of butyric acid are also formed. 

Chemical Properties. Neopentyl glycol can undergo typical glycol reactions such as esterification (qv), etherification, condensation, and oxidation. When basic kinetic studies of the esterification rate were carried out for neopentyl glycol, the absolute esterification rate of neopentyl glycol with / -butyric acid was approximately 20 times that of ethylene glycol with / -butyric acid (7). 

Between 6 and 30% of the radical attack on butane may occur at the primary hydrogen atoms (213). Since ca 6% of the butane goes to or through butyric acid (22), the middle of this range does not seem unreasonable. Because it is much more resistant to oxidation than its precursors or coproducts, acetic acid (qv) is the main product of butane LPO. 

Production of maleic anhydride by oxidation of / -butane represents one of butane s largest markets. Butane and LPG are also used as feedstocks for ethylene production by thermal cracking. A relatively new use for butane of growing importance is isomerization to isobutane, followed by dehydrogenation to isobutylene for use in MTBE synthesis. Smaller chemical uses include production of acetic acid and by-products. Methyl ethyl ketone (MEK) is the principal by-product, though small amounts of formic, propionic, and butyric acid are also produced. / -Butane is also used as a solvent in Hquid—Hquid extraction of heavy oils in a deasphalting process. 

PMMA is not affected by most inorganic solutions, mineral oils, animal oils, low concentrations of alcohols paraffins, olefins, amines, alkyl monohahdes and ahphatic hydrocarbons and higher esters, ie, >10 carbon atoms. However, PMMA is attacked by lower esters, eg, ethyl acetate, isopropyl acetate aromatic hydrocarbons, eg, benzene, toluene, xylene phenols, eg, cresol, carboHc acid aryl hahdes, eg, chlorobenzene, bromobenzene ahphatic acids, eg, butyric acid, acetic acid alkyl polyhaHdes, eg, ethylene dichloride, methylene chloride high concentrations of alcohols, eg, methanol, ethanol 2-propanol and high concentrations of alkahes and oxidizing agents. 

Thus, -butyl [71-36-3] [71-36-3] and isobutyl alcohol [78-83-1] [78-83-1] are obtained by hydrogenation of their respective aldehydes and butyric and isobutyric acid are produced by oxidation. 

Oxidation of butyraldehyde to butyric acid [107-92-6]is most commonly carried out employing air or oxygen as the oxidant. Alternatively, organic oxidants, eg, cumene hydroperoxide, can also be employed effectively to give high yields of butyric acid, (4). 

Several species of bacteria under suitable conditions cause / -butyraldehyde to undergo the Canni22aro reaction (simultaneous oxidation and reduction to butyric acid and butanol, respectively) this reaction can also be cataly2ed by Raney nickel (7). The direct formation of butyl butyrate [109-21 -7] or isobutyl isobutyrate [97-85-8](Vish.ch.erik.o reaction) from the corresponding aldehyde takes place rapidly with aluminum ethylate or aluminum butyrate as catalyst (8). An essentially quantitative yield of butyl butyrate, CgH2 02, from butyraldehyde has been reported usiag a mthenium catalyst, RuH,[P(C,H,)3], (9). 

Butyric acid, the simple oxidation product of -butyraldehyde, is used chiedy in the production of cellulose acetate butyrate [9004-36-8]. Sheets of cellulose acetate butyrate are used for thermoformed sign faces, bUster packaging, goggles, and face shields. 

Butyric acid is made by air-oxidation of butyraldehyde, which is obtained by appHcation of the oxo synthesis to propylene. Isobutyric acid is made from isobutyraldehyde, a significant product in the synthesis of butyraldehyde (see Butyraldehydes). Butyraldehyde is also used to make 2-ethylhexanoic acid. 

Salts of neodecanoic acid have been used in the preparation of supported catalysts, such as silver neodecanoate for the preparation of ethylene oxide catalysts (119), and the nickel soap in the preparation of a hydrogenation catalyst (120). Metal neodecanoates, such as magnesium, lead, calcium, and zinc, are used to improve the adherence of plasticized poly(vinyl butyral) sheet to safety glass in car windshields (121). Platinum complexes using neodecanoic acid have been studied for antitumor activity (122). Neodecanoic acid and its esters are used in cosmetics as emoUients, emulsifiers, and solubilizers (77,123,124). Zinc or copper salts of neoacids are used as preservatives for wood (125). 

Oxidized castor oils are excellent nonmigrating, nonvolatile plasticizers (qv) for ceUulosic resins, poly(vinyl butyral), polyamides, shellac, and natural and synthetic mbber (see Rubber, natural). The high viscosity products are also used as tackifiers in gasket compounds and adhesives (qv) because of good oil and solvent resistance. They also serve as excellent pigment grinding media and as a base for inks (qv), lubricating oils, and hydrauHc oils (62). 

Cellulose acetate butyrate is not affected by dilute acids and alkalies or gasoline, but chlorinated solvents cause some swelhng. Nylons resist many organic solvents but are attacked by phenols, strong oxidizing agents, and mineral acids. 

Butyroin has been prepared by reductive condensation of ethyl butyrate with sodium in xylene, or with sodium in the presence of chloro-trimethylsilane. and by reduction of 4,5-octanedlone with sodium l-benzyl-3-carbamoyl-l,4-dihydropyridine-4-sulfinate in the presence of magnesium chloride or with thiophenol in the presence of iron polyphthalocyanine as electron transfer agent.This acyloin has also been obtained by oxidation of (E)-4-octene with potassium permanganate and by reaction of... 

Methylsuccinic acid has been prepared by the pyrolysis of tartaric acid from 1,2-dibromopropane or allyl halides by the action of potassium cyanide followed by hydrolysis by reduction of itaconic, citraconic, and mesaconic acids by hydrolysis of ketovalerolactonecarboxylic acid by decarboxylation of 1,1,2-propane tricarboxylic acid by oxidation of /3-methylcyclo-hexanone by fusion of gamboge with alkali by hydrog. nation and condensation of sodium lactate over nickel oxide from acetoacetic ester by successive alkylation with a methyl halide and a monohaloacetic ester by hydrolysis of oi-methyl-o -oxalosuccinic ester or a-methyl-a -acetosuccinic ester by action of hot, concentrated potassium hydroxide upon methyl-succinaldehyde dioxime from the ammonium salt of a-methyl-butyric acid by oxidation with. hydrogen peroxide from /9-methyllevulinic acid by oxidation with dilute nitric acid or hypobromite from /J-methyladipic acid and from the decomposition products of glyceric acid and pyruvic acid. The method described above is a modification of that of Higginbotham and Lapworth. ... 

Poly(ethylene terephtlhalate) Phenol-formaldehyde Polyimide Polyisobutylene Poly(methyl methacrylate), acrylic Poly-4-methylpentene-1 Polyoxymethylene polyformaldehyde, acetal Polypropylene Polyphenylene ether Polyphenylene oxide Poly(phenylene sulphide) Poly(phenylene sulphone) Polystyrene Polysulfone Polytetrafluoroethylene Polyurethane Poly(vinyl acetate) Poly(vinyl alcohol) Poly(vinyl butyral) Poly(vinyl chloride) Poly(vinylidene chloride) Poly(vinylidene fluoride) Poly(vinyl formal) Polyvinylcarbazole Styrene Acrylonitrile Styrene butadiene rubber Styrene-butadiene-styrene Urea-formaldehyde Unsaturated polyester... 

Cellulose Esters Epoxy Resins Lignins Polystyrene Poly (2-vinyl pyridine) Polyvinyl Chloride Polymethyl methacrylate Polyphenylene Oxide Phenolics Polycarbonate Polyvinyl Acetate, etc. Polyvinyl butyral SBR rubber, etc., etc. 

Water-soluble polymers eomprise a major elass of polymerie materials and are used in a wide variety of applieations. Synthetie water-soluble polymers inelude poly(vinyl aleohol), poly(aerylamide), poly(aerylie aeid), poly(ethylene oxide), poly(vinyl pyrrolidone), eellulosies, and many eopolymers of these types. Their end uses are quite varied and their applieations depend mainly on their viseosify-ing, rheologieal, and surfaee-aetive properties (1). For example, poly (vinyl aleohol) is used in adhesives, fibers, textile and paper sizing, paekaging, as a stabilizer for emulsion polymerization, and as a preeursor for the manufaeture of poly(vinyl butyral), whieh is used in automotive windshields. Poly(vinyl aleohol) is also the world s largest volume, eommodity, water-soluble polymer. 

Acetanilide and maleic acid are condensed to give /3-(p-acetaminoben2oyl)acrvlic acid which is hydrogenated to give methyl- y-(p-aminophenyl)butyrate. That is reacted with ethylene oxide and then with phosphorus oxychloride to give the methyl ester which is finally hy-droly2ed to give chlorambucil. 

Moisture Deteriorating effects of moisture are well known as reviewed early in this chapter (OTHER BEHAVIOR, Drying Plastic). Examples for high moisture applications include polyphenylene oxide, polysulfone, acrylic, butyrate, diallyl phthalate, glass-bonded mica, mineral-filled phenolic, chlorotrifluoroethylene, vinylidene, chlorinated polyether chloride, vinylidene fluoride, and fluorocarbon. Diallyl phthalate, polysulfone, and polyphenylene oxide have performed well with moisture/steam on one side and air on the other (a troublesome... 

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