N Caproic acid

Fit a reflux condenser into the short neck of a 125 ml. Claisen flask, a separatory funnel into the long neck, and plug the side arm with a small cork (compare Fig. Ill, 31, 1). Place 58 g. (62 ml.) of commercial n-caproic acid (1) in the flask and heat on a water hath. Add 75 g. (46 ml.) of redistilled thionyl chloride through the separatory funnel during 45 minutes shake the flask from time to time to ensure thorough mixing. Reflux the mixture for 30 minutes. Arrange the apparatus for distillation from an air bath (Fig. II, 5, 3) the excess of thionyl chloride passes over flrst, followed by n-caproyl chloride at 145-155° (mainly at 150-155°). The yield of acid chloride is 56 g. 

Myristic acid from hexanoic acid and methyl hydrogen sebacate). Dissolve 23-2 g. of redistilled hexanoic acid (n-caproic acid), b.p. 204-5-205-5°l760 mm., and 21-6 g. of methyl hydrogen sebacate in 200 ml. of absolute methanol to which 0 -13 g. of sodium has been added. Electrolyse at 2-0 amps., whilst maintaining the temperature between 30° and 40°, until the pH is about 8-0 (co. 6 hours). Neutralise the contents of the electrolysis cell with a little acetic acid and distil off the methyl alcohol on a water bath. Dissolve the residue in 200 ml. of ether, wash with three 50 ml. portions of saturated sodium bicarbonate solution, once with water, dry with anhydrous magnesium sulphate, and distil with the aid of a fractionating column (see under Methyl hydrogen adipate). Collect the w-decane at 60°/10 mm. (3-0 g.), the methyl myristate at 158-160°/ 10 mm. (12 - 5g.) and dimethyl hexadecane-1 16-dicarboxylateat 215-230°/ 7 mm. (1 -5 g.)... 

Acids. Acetic acid n-Caproic acid Benzoic acid Phenylacetic acid Succinic acid Adipic acid Anthranilic acid. 

FIGURE 9 Capillary zone electrophoresis of eight recombinant human anti bod ies/anti body fragments. Capillary BioCAP XL coated capillary (50 pm x 47 cm) 45 mM g-amino-n-caproic acid/ acetic acid, pH 4.5, 0.1% HPMC voltage 30kV, normal polarity capillary temperature 20°C detection, UV at 214 nm. 

Fig. 8.3. GC chromatogram of mixed silage juice standards using a Carbopack B-DA column. Identity and concentrations (before diluting 4 1 standard 0.3 M oxalic acid) a, ethanol, 1 mg mM b, acetic acid, 1.25 mg mM c, propionic acid, 0.25 mg ml" d, isobutyric acid, 0.25 mg mM e, n-butyric acid, 0.25 mg mM f, pivalic acid (internal standard), 0.4 mg mM g, isovaleric acid, 0.25 mg mM h, lactic acid, 10 mg mM i, n-valeric acid, 0.25 mg mM j, isocaproic acid, 0.25 mg mM k, n-caproic acid, 0.25 mg mM.

Alanine, aspartic acid, glutamic acid, tyrosine, leucine, phenylalanine and also a-amino-n-caproic acid and a-aminobutyric acid have in this way been separated by Fischer into their optically active isomers. To these must be added ornithine which was synthesised by Sorensen in 1903, and separated into d- and 1-ornithine in 1905. 

In the case of molecules which do not dissociate, the electromotive force must be due to the orientation of the molecules in the surface layer, which molecules must have a definite electric moment. In the few cases where the electromotive force can be accurately compared with the surface concentration such as n-but3rric, ri-valeric and n-caproic acids, the E.M.F. is almost approximately proportional to the surface concentration F, as would be the case if the moment of a molecule were independent of the proximity of its neighbours. 

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