N-Butyric acid

Let us consider a specific example, viz., the extraction of a solution of 4 Og. of n-butyric acid in 100 ml. of water at 15° with 100 ml. of benzene at 15°. The partition coefficient of the acid between benzene and water may be taken as 3 (or J between water and benzene) at 15°. For a single extraction with benzene, we have ... 

Hence one extraction with 100 ml. of benzene removes 3 0 g. (or 75 per cent.) of the n-butyric acid, whilst three extractions remove 3 5 g. (or 87-5 per cent.) of the total acid. This clearly shows the greater efficiency of extraction obtainable with several extractions when the total volume of solvent is the same. Moreover, the smaller the distribution coefficient between the organic solvent and the water, the larger the number of extractions that will be necessary. 

Ethyl n-butyrate. Use a mixture of 88 g. (92 ml.) of n-butyric acid, 23 g. (29 ml.) of ethanol and 9 g. (5 ml.) of concentrated sulphuric acid. Reflux for 14 hours. Pour into excess of water, wash several times with water, followed by saturated sodium bicarbonate solution until all the acid is removed, and finally with water. Dry with anhydrous magnesium sulphate, and distU. The ethyl n-but3rrate passes over at 119 5-120-5°, Yield 40 g. An improved yield can be obtained by distilhng the reaction mixture through an efficient fractionating column until the temperature rises to 125°, and purifying the crude ester as detailed above under methyl acetate. 

The ketones are readily prepared, for example, acetophenone from benzene, acetyl chloride (or acetic anhydride) and aluminium chloride by the Friedel and Crafts reaction ethyl benzyl ketones by passing a mixture of phenylacetic acid and propionic acid over thoria at 450° and n-propyl- p-phenylethylketone by circulating a mixture of hydrocinnamic acid and n-butyric acid over thoria (for further details, see under Aromatic Ketones, Sections IV,136, IV,137 and IV,141). 

Ethanol, acetaldehyde, acetic acid, acetone, glycerol, n - butanol, n - butyric acid, amyl alcohols, oxalic acid, lactic acid, citric acid, amino acids, antibiotics, vitamins... 

Acetyl-a-amino-n-butyric acid [34271-24-4] M 145.2, pK 3.72. Crystd twice from water (charcoal) and air dried [King and King J Am Chem Soc 78 1089 7956]. 

Phenylcyclohexane and succinic acid (8ernstein Acid) anhydride are reacted in the presence of AICI3 to give 4-(4 -cvclohexvlphenvl)-4-keto-n-butyric acid. 

OH3COOH + CHgCHgCHgCOOH CHgCOCHgCHgCHg + CO -f HgO Acetic acid n-Butyric acid Methyl n-propyl ketone... 

Figure 9 Three-dimensional cationic CITP of (A) blank (B) lysozyme (LYSO), creatinine (CREAT), conalbumin (CAL), y-amino-n-butyric acid (GABA), and ovalbumin (OVA) (C) OVA spiked with CREAT and GABA. Capillary 90 cm (length to the detector, 70 cm) x 75 p i.d. leader 10 mM potassium acetate and acetic acid with 0.3% HPMC, pH 4.75 terminator 10 mM acetic acid sample 10 to 30 mg/ml proteins dissolved in leader without HPMC voltage 20 kV. (From Gebauer, P. and Thormann, W.,. Chromatogr., 558, 423, 1991. With permission.)...

Fine chemicals These are produced in small volumes and purchased on the basis of chemical composition, purity and price. Examples are chloropropylene oxide (used for the manufacture of epoxy resins, ion-exchange resins and other products), dimethyl formamide (used, for example, as a solvent, reaction medium and intermediate in the manufacture of pharmaceuticals), n-butyric acid (used in beverages, flavorings, fragrances and other products) and barium titanate powder (used for the manufacture of electronic capacitors). 

Formic acid Oxalic acid Malonic acid Propionic acid n-Butyric acid Unknown... 

Ito et al.40 examined the electrochemical reduction of C02 in dimethylsulfoxide (DMSO) with tetraalkylammonium salts at Pb, In, Zn, and Sn under high C02 pressures. At a Pb electrode, the main product was oxalic acid with additional products such as tartaric, malonic, glycolic, propionic, and n-butyric acids, while at In, Zn, and Sn electrodes, the yields of these products were very low (Table 3), and carbon monoxide was verified to be the main product even at a Pt electrode, CO was mainly produced in nonaqueous solvents such as acetonitrile and DMF.41 Also, the products in propylene carbonate42 were oxalic acid at Pb, CO at Sn and In, and substantial amounts of oxalic acid, glyoxylic acid, and CO at Zn, indicating again that the reduction products of C02 depend on the electrode materials used. 

Hydroxy-n-butyric acid 3 Carbapenem Antibacterial Hydroxylation Candida rugosa Single-stage fermentation [4]... 

New analyses of material from the interior of the Orgeuil and Ivona meteorites show the presence of P-alanine, glycine and y-amino-n-butyric acid as the main components (0.6-2.0ppm) traces of other amino acids were also detected. The amino acids were present as racemic mixtures, i.e., d/l = 1, so that an extraterrestrial origin can be assumed (Ehrenfreund et al., 2001). 

Malcolm (1973, 1975) reported possible observable differences between the pressure-area curves of poly(L-alanine) mixed with poly(D-a-amino-n-butyric acid) and the corresponding mixture containing poly(D-alanine). Shafer (1974) observed differences in the film pressure between (/ )-phosphatidyl serine with poly-L-lysine and the corresponding film with poly-D-lysine injected under the film. 

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