Caproamide

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. 

Place 125 ml. of concentrated ammonia solution (sp. gr. 0-88) in a 600 ml. beaker and surround the latter with crushed ice. Stir the ammonia solution mechanically, and introduce the n-caproyl chloride slowly by means of a suitably supported separatory funnel with bent stem. The rate of addition must be adjusted so that no white fumes are lost. The amide separates immediately. Allow to stand in the ice water for 15 minutes after all the acid chloride has been introduced. Filter oflF the amide at the pump use the flltrate to assist the transfer of any amide remaining in the beaker to the Alter (2). Spread the amide on sheets of Alter or drying paper to dry in the air. The crude n-capro-amide (30 g.) has m.p. 98-99° and is sufficiently pure for conversion into the nitrile (Section 111,112) (3). Recrystallise a small quantity of the amide by dissolving it in the minimum volume of hot water and allowing the solution to cool dry on filter paper in the air. Pure n-caproamide has m.p. 100°. 

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The filtrate will deposit small amounts of n-caproamide upon concentration to half its original volume. 

The student should carry out the following simple experiments with acetamide or with any other ahphatic amide, e.g., n-caproamide they illustrate some of the general reactions of primary ahphatic amides. 

Place 29 g. of n-caproamide (Section 111,109) into a 200 ml. distilling flask, and assemble the apparatus shown in Fig. Ill, 28, 1. Remove the trap momentarily and introduce 45 g. (27-5 ml.) of redistilled thionyl chloride no apparent reaction takes place in the cold. Warm the mixture on a water bath or by means of a small flame for 1 hour. Arrange the apparatus for distillation and distil oflF the excess of thionyl chloride (t.c., until the temperature reaches about 90°) and allow to cool. When cold, transfer the residue to a 100 ml. distilling flask (1). Distil from an air bath (Fig. II, 5, 3) the n-capronitrile passes over at 161-163° (2). The yield is 21 g. 

Into a 1500 ml. round-bottomed flask place 97-5 g. of finely-powdered sodium cyanide (1), 125 ml. of water, and a few chips of porous porcelain. Attach a reflux condenser and warm on a water bath until all the sodium cyanide dissolves. Introduce a solution of 250 g. (196 ml.) of n-butyl bromide (Sections 111,35 and 111,37) in 290 ml. of pure methyl alcohol, and reflux gently on a water bath for 28-30 hours. Cool to room temperature and remove the sodium bromide which has separated by filtration through a sintered glass funnel at the pump wash the crystals with about 100 ml. of methyl alcohol. Transfer the filtrate and washings to From n caproamide by SOClj method. 

Nitro compounds. Nitromethane Nitrobenzene ni-Dinitrobenzene. Amides and imides. Acetamide re-Caproamide Acetanilide Benz-anilide Phthalimide. 

M-Hexyl alcohol has been prepared by the reduction of ethyl caproate by means of sodium and absolute alcohoB alone or in anhydrous ammonia solution by the reduction of -caproamide by means of sodium and absolute alcohol by the reduction of -caproaldehyde by means of sodium amalgam in dilute sulfuric acid and by means of living yeast, It has also been produced by the action of nitrous acid upon w-hexylamine by the action of sodium upon a mixture of ethyl alcohol and M-butyl alcohol ... 

No counterpart for such regularities is found in synthetic polymers. The hydrolysis of poly-6-caproamide... 

These were prepared by efficiently interhnking pairs of carboxyl end groups in fibers extruded from tetra-chain and from octachain poly- -caproamides (see p. 

Fig. 135.—The relationship between the equilibrium retractive force T(x (in lbs./in.2) at 241 °C for various multilinked poly (e-caproamides) at the extensions (a) indicated, and their equilibrium swelling ratios in m-cresol at 30°C. O, tetralinked polymers octa-linked polymers. The lines have been calculated according to Eq. (41), with appropriate revision for the octafunctional case (broken lines), an arbitrary value being assigned to the parameter Xi for each elongation. (Schaefgen and Flory.33)...

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