Sodium hydroxide boiling point

Place in a small flask 1 cc. of acetone, 4 cc. of water, 4 cc. of benzaldehyde, 20 cc. of alcohol, and 5 cc. of a 10 per cent solution of sodium hydroxide. Boil gently for 5 minutes. Cool and shake. Filter off the crystals and wash them with 20 cc. of cold alcohol. Recrystallize from 20 cc. of boiling alcohol. Let the solution cool. Filter and wash with 10 cc. of cold alcohol. Dry on a porous plate and determine the melting-point of the crystals. Dibenzalacetone crystallizes in yellow plates and melts at 111°-112°. 

If, however, the sodium hydroxide is removed by allowing it to react with excess of an ester of high boiling point, such as ethyl succinate or ethyl phthalate, super-dry ethyl alcohol may be obtained ... 

Reflux a mixture of 68 g. of anhydrous zinc chloride (e.g., sticks), 40 ml. (47 -5 g.) of concentrated hydrochloric acid and 18-5 g. (23 ml.) of sec.-butyl alcohol (b.p. 99-100°) in the apparatus of Fig. 777, 25, 1 for 2 hours. Distil oflF the crude chloride untU the temperature rises to 100°. Separate the upper layer of the distillate, wash it successively with water, 5 per cent, sodium hydroxide solution and water dry with anhydrous calcium chloride. Distil through a short column or from a Claisen flask with fractionating side arm, and collect the fraction of b.p. 67-70° some high boiling point material remains in the flask. Redistil and collect the pure cc. butyl chloride at 67-69°. The yield is 15 g. 

Dissolve or suspend 0 - 5 g. of the acid in 5 ml. of water in a small conical flask, add a drop or two of phenolphthalein indicator, and then 4-5 per cent, sodium hydroxide solution until the acid is just neutrahsed. Add a few drops of very dilute hydrochloric acid so that the final solution is faintly acid (litmus).f Introduce 0-5 g. of p-bromophenacyl bromide (m.p. 109°) dissolved in 5 ml. of rectified (or methylated) spirit, and heat the mixture under reflux for 1 hour if the mixture is not homogeneous at the boiling point or a solid separates out, add just sufficient alcohol to produce homogeneity. [Di- and tri-basic acids require proportionately larger amounts of the reagent and longer refluxing periods.] Allow the solution to cool, filter the separated crystals at the pump, wash with a little alcohol and then with water. Recrystallise from dilute alcohol dissolve the solid in hot alcohol, add hot water until a turbidity just results, clear the latter with a few drops of alcohol, and allow to cool. Acetone may sometimes be employed for recrystallisation. 

If pure 3-bromo-4-aminotoluene is required, the crude base may be purified either by steam distillation or, more satisfactorily, by distillation under reduced pressure. The oil is dried with 5 g. of sodium hydroxide pellets, and distilled under reduced pressure from a Claisen fiask with a fractionating side arm a little p-tolui-dine may be present in the low boiling point fraction, and the pure substance is collected at 92-94°/3 inin. or at 120-122°/30 mm. The purified amine solidifies on cooling and melts at 17-18°. 

Sometimes the reaction stops suddenly it is then necessary to add a further 10 ml. of 20 per cent, sodium hydroxide solution and warm to the boiling point this causes the reaction to continue. Occasionally, the reduction becomes very vigorous a wet towel and a bath of ice water should be kept close at hand. 

Dissolve 5 g. of phenol in 75 ml. of 10 per cent, sodium hydroxide solution contained in a wide-mouthed reagent bottle or conical flask of about 200 ml. capacity. Add 11 g. (9 ml.) of redistilled benzoyl chloride, cork the vessel securely, and shake the mixture vigorously for 15-20 minutes. At the end of this period the reaction is usually practically complete and a sohd product is obtained. Filter oflf the soUd ester with suction, break up any lumps on the filter, wash thoroughly with water and drain well. RecrystaUise the crude ester from rectified (or methylated) spirit use a quantity of hot solvent approximately twice the minimum volume required for complete solution in order to ensure that the ester does not separate until the temperature of the solution has fallen below the melting point of phenyl benzoate. Filter the hot solution, if necessary, through a hot water funnel or through a Buchner funnel preheated by the filtration of some boiling solvent. Colourless crystals of phenyl benzoate, m.p. 69°, are thus obtained. The yield is 8 g. 

Aromatic nitriles are generally liquids or low melting point solids, and usually have characteristic odours. They give no ammonia with aqueous sodium hydroxide solution in the cold, are hydrolysed by boiling aqueous alkali but more slowly than primary amides ... 

A mixture of 3.0 g (0.019 mol) of 6-amino-4-chloro-1,2-dihydro-1 -hydroxy-2-iminopyrimi-dlneand 35 ml of piperidine is refluxed for 1.5 hours, cooled and filtered. The sol id is shaken for 20 minutes in a solution of 08 g of sodium hydroxide in 30 ml of water and filtered. The solid is washed with water and extracted with 800 ml of boiling acetonitrile and filtered to yield 3.5 g (89%) yield of 6-amino-1,2-dihydro-l-hydroxy-2-imino-4-piperidinopyrimidine, melting point 248°C, decomposition at 259°C to 261°C. 

Ethyl-2-methyl-3-(10,11) -dihydro-5H-dibenzo [a,d] cycloheptene-5-ylidene)-1 -pyrrolinium iodide (4.7 g) was dissolved in 7 cc of methanol. To this solution there were added 1.4 g of sodium boron hydride within about 80 minutes with stirring and stirring of the solution was continued for two hours to complete the reaction. The reaction mixture was acidified with 10% aqueous hydrochloric acid solution and then the methanol was distilled off. The residual solution was alkalized with 20% aqueous sodium hydroxide solution and extracted with ether. The ether layer was dried over magnesium sulfate and the ether was distilled off. The resulting residue was further distilled under reduced pressure to yield 2.0 g of 1-ethyl-2-methyl-3-(10,11 ) dihydro-5H-dibenzo[a,d]cycloheptene-5-ylidene)pyrrolidine (boiling point 167°C/4 mm Hg.). 

Preparation of 3-Amino-5-Methylisox3Zo/e 1.7 grams of ethyl 5-methylisoxa2ole-3-car-bamate was heated on a boiling water-bath with 5 cc of a 10% aqueous sodium hydroxide solution for 8 hours, then the reaction mixture was extracted several times with ether or benzene and the extract was cooled followed by the removal of the solvent and drying. The residue was solidified after a while and gave prismatic crystals, melting point 61° to 62°C, of 3-amino-5-methylisoxazole by recrystallization from benzene. 

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