Hydrochloride hydroxylamine

Metallic Derivatives, (a) Cuprous Acetylide. CujCg. Prepare an ammoniacal solution of cuprous chloride by first adding dilute ammonia to 2-3 ml. of dilute copper sulphate solution until the initial precipitate just redissolves and a clear deep-blue solution is obtained now add an aqueous solution of hydroxylamine hydrochloride drop by drop with shaking until the solution becomes first green and then completely colourless, the cupric salt being thus reduced to the cuprous derivative. 

Required Hydroxylamine hydrochloride, 12-5 g. sodium hydroxide, 7 g. dry acetone, 12 ml-... 

Prepare a solution of 12 5 g. of hydroxylamine hydrochloride in 20 ml. of water contained in a too ml. conical flask. Dissolve 7 g. of powdered sodium hydroxide in 20 ml. of water, cool the solution in ice-water, and then add it to that of the hydroxylamine hydrochloride. Place a thermometer in the mixed solution, and chill the flask in ice-water until the temperature of the solution is between 5 and 10 . Now add 12 ml. (9 5 gO of dry acetone (preferably from a burette to ensure... 

Required Anthranilic acid, 20 g. anhydrous sodium carbonate, 7 5 g, sodium nitrite, 12 g. concentrated hydrochloric acid, 190 ml. crystalline copper sulphate, 50 g. concentrated ammonia, 85 ml, hydroxylamine hydrochloride, 14-5 g. (or hydroxylamine sulphate, 17-4 g.) acetic acid, 10-20 ml,... 

B) Preparation of the Cuprous Solution, Add 85 ml. of concentrated ammonia solution (d, o-o88) to a solution of 50 g. of crystalline copper sulphate in 200 ml. of water, and cool to 10 . Dissolve 14 5 g. of hydroxylamine hydrochloride (or 17-4 g. of the sulphate) in 50 ml. of water, cool to 10 , and add a solution of 9 g. of sodium hydroxide in 30 ml. of water. Without delay add this hydroxylamine solution with stirring to the copper solution, which will be immediately reduced, but will retain a blue colour. 

Required Cyclohexanone, 20 g. hydroxylamine hydrochloride, 17 g. anhydrous sodium carbonate, 13 g. concentrated sulphuric acid, 50 ml. 25% aqueous potassium hydroxide solution, approx. 200 ml. chloroform, 120 ml. 

Cyclohexanone oxime. Add 20 g. (21 ml.) of cyclohexanone to a solution of 17 g. of hydroxylamine hydrochloride in 40 ml. of water, and cool the mixture in ice-water. Add a solution of 13 g. of anhydrous sodium carbonate in 40 ml. of water slowly to the mixture, stirring the latter with a 100° thermometer, and maintaining the temperature of the mixture at 20-25° meanwhile. The oxime rapidly separates. Stir the complete mixture at intervals, and after 10 minutes filter the oxime at the pump, drain thoroughly and dry it in a (vacuum) desiccator. Yield of crude oxime, 20 g. Recrystallise from petroleum (b.p. 100-120 ) and dry over paraffin wax (p. 19). Yield of pure oxime, 16 g., m.p. 88°. 

To a few drops of the ester, add 0 2 g. of hydroxylamine hydrochloride and about 5 ml. of 10% NaOH solution and gently boil the mixture for 1-2 minutes. Cool and acidify with HCl, cool again and then add a few drops of FeClj solution. A violet or deep red-brown colour develops immediately. 

Hydroxamic acid formation. To 0 1 g. of acetic anhydride, add 0 1 g. of hydroxylamine hydrochloride and 5 ml. of 10% NaOH solution. Boil the mixture for i minute, cool and acidify with dilute... 

B) Oximes. Dissolve i g. of the quinone in 5 ml. of glacial acetic acid. Dissolve i g. of hydroxylamine hydrochloride in 10 ml. of 10% aqueous sodium acetate solution and shake the mixture for 5 minutes. Cool, filter off the dioxime and recrystallise from ethanol. (M.ps., p. 549.)... 

Dissolve 5 g. of hydroxylamine hydrochloride in 10 ml. of water in a small conical flask and add a solution of 3 g. of sodium hydroxide in 10 ml. of water. Cool the solution in cold or ice water, and add 6 g. (7-6 ml.) of acetone slowly. Cool the flask, shake well, and leave overnight, during which time the oxime may crystallise out. If no crystals appear, cork the flask and shake vigorously when the acetoxime usually separates as colourless crystals. Filter the crystals at the pump, dry rapidly between filter paper (yield 2- 6 g.) and determine the m.p. (59°). Extract the filtrate with two 20 ml. portions of ether, and remove the solvent a further 0 - 5 g. of acetoxime (m.p. 60°) is obtained. Recrystallise from light petroleum, b.p. 40-60° CAUTION inflammable) to obtain the pure acetoxime, m.p. 60°. Acetoxime sublimes when left exposed to the air. 

Dissolve 2 5 g. of hydroxylamine hydrochloride and 4 g. of crystallised sodium acetate in 10 ml. of water in a small flask or in a test-tube. Warm the solution to about 40° and add 2 5 g. of cyclohexanone. Stopper the vessel securely with a cork and shake vigorously for a few minutes the oxime soon separates as a crystalline solid. Cool in ice, filter the crystals at the pump, and wash with a little cold water. RecrystaUise from light petroleum, b.p. 60-80°, and dry the crystals upon filter paper in the air. The yield of pure cycZohexanone oxime, m.p. 90°, is 2 -5 g. 

Oximes. The method given for semicarbazones (see 2) may be employed use 1 g. of hydroxylamine hydrochloride, 2 g. of crystallised sodium acetate and 0 5 g. of the aldehyde or ketone. It is usually advisable to warm on a water bath for 10 minutes. 

For water insoluble aldehydes or ketones, the following alternative procedure may be used. Reflux a mixture of 0-6 g. of the aldehyde or ketone, 0 5 g. of hydroxylamine hydrochloride, 5 ml. of ethanol and 0 5 ml. of pyridine on a water bath for 15-60 minutes. Remove the alcohol either by distillation (water bath) or by evaporation of the hot solution in a stream of air (water pump). Add 5 ml. of water to the cooled residue, cool in an ice bath and stir until the oxime crystallises Filter off the solid, wash it with a little water and dry. Recrystallise from alcohol (95 per cent, or more dilute), benzene, or benzene - light petroleum (b.p. 60-80°). 

In a 250 ml. conical flask mix a solution of 14 g. of sodium hydroxide in 40 ml. of water and 21 g. (20 ml.) of pure benzaldehyde (Section IV,115). Add 15 g. of hydroxylamine hydrochloride in small portions, and shake the mixture continually (mechanical stirring may be employed with advantage). Some heat is developed and the benzaldehyde eventually disappears. Upon coohiig, a crystalline mass of the sodium derivative separates out. Add sufficient water to form a clear solution, and pass carbon dioxide into the solution until saturated. A colourless emulsion of the a or syn-aldoxime separates. Extract the oxime with ether, dry the extract over anhydrous magnesium or sodium sulphate, and remove the ether on a water bath. Distil the residue under diminished pressure (Fig. 11,20, 1). Collect the pure syn-benzaldoxime (a-benzald-oxime) at 122-124°/12 mm. this gradually solidifies on cooling in ice and melts at 35°. The yield is 12 g. 

Oximes (compare Section III,74,B). The following procedure has wide application. Dissolve 0-5 g. of hydroxylamine hydrochloride in 2 ml. of water, add 2 ml. of 10 per cent, sodium hydroxide solution and 0-2 g. of the aldehyde (or ketone). If the latter is insoluble, add just sufficient alcohol to the mixture to give a clear solution. Heat the mixture under reflux for 10-15 minutes, and then cool in ice. If crystals separate, filter these off, and recrystallise from alcohol, dilute alcohol, benzene or light petroleum (b.p. 60-80°). If no solid separates on cooling, dilute with 2-3 volumes of water, filter the precipitated sohd, and recrystallise. 

Bfflizophenone condenses with hydroxylamine hydrochloride in the presence of excess of sodium hydroxide solution to 3deld benzophenone oxime, m.p. 142° ... 

Veratronitrile, Dissolve 83 g. of veratraldehyde in 200 ml. of warm rectified spirit in a 1 litre bolt-head flask, and add a warm solution of 42 g. of hydroxylamine hydrochloride in 50 ml. of water. Mix thoroughly and run in a solution of 30 g. of sodium hydroxide in 40 ml. of water. Allow the mixture to stand for 2-5 hours, add 250 g. of crushed ice, and saturate the solution with carbon dioxide. The aldoxime separates as an oil allow the mixture to stand for 12-24 hours in an ice chest or refrigerator when the oil will sohdify. Filter off the crystalline aldoxime at the pump, wash well with cold water, and dry in the air upon filter paper. The yield of veratraldoxime is 88 g. 

The diacetyl monoxime condenses readily with hydroxylamine hydrochloride or sulphate with the formation of dimethylglyoxime (diacetyl dioxime) ... 

Method 1. Dissolve 25 0 g. of salicylaldehyde (Section IV,122) in 215 ml. of 2N sodium hydroxide solution, add 12 05 g. of hydroxylamine hydrochloride, and warm the mixture for 30 minutes on a water bath. Acidify with acetic acid and cool in ice the salicylaldoxime separates as a congealed oil. Recrystalhae from chloroform - light petroleum (b.p. 40-60°). The yield of salicylaldoxime (colourless crystals, m.p. 57°) is 5 g. 

In a 250 ml. bolt-head flask, fitted with a reflux condenser, place a mixture of 10 g. of benzoin (Section IV,125) and 20 g. (25 ml.) of rectified spirit together with an aqueous solution of 8 0 g. of hydroxylamine hydrochloride which has previously been neutralised with 4-4 g. of sodium hydroxide. Reflux for 60 minutes. Add water to precipitate the benzoinoxime, and cool in an ice bath. Filter the solid with suction at the pump, wash it with water, and recrystaUise from dilute alcohol. Alternatively, the dry sohd may be recrystalhsed from ether. The yield of pure a-benzoinoxime, m.p. 151°, is 5 g. 

B. Mix 1 drop or several small crystals (ca. 0 05 g.) of the compound with 1 ml. of 0-5 V hydroxylamine hydrochloride in 95 per cent, ethanol and add 0-2 ml ot aqueous sodium hydroxide. Heat the mixture to boiling and, after the solution has cooled slightly, add 2 ml. of N hydrochloric acid. If the solution is cloudy, add 2 ml. of 95 per cent, ethyl alcohol. Observe the colour produced when I drop of 6 per cent, ferric chloride solution is added. If the resulting colour does not persist, continue to add the reagent dropwise until the observed colour pervades the entire solution. Usually only 1 drop of the ferric chloride solution is necessary. Compare the colour with that produced in test. 4. A positive test will be a distinct burgundy or magenta colour as compared with the yellow colour observed when the original compound is tested with ferric chloride solution in the presence of acid. 

The purity of a synthetic preparation of methylethyl ketone (C4H8O) can be determined by reacting the ketone with hydroxylamine hydrochloride, liberating HCl (see Table 9.10). In a typical analysis, a 3.00-mL sample was diluted to 50.00 ml and treated with an excess of hydroxylamine hydrochloride. The liberated HCl was titrated with 0.9989 M NaOH, requiring 32.68 ml to reach the end point. Report the percent purity of the sample, given that the density of methylethyl ketone is 0.805 g/mL. 

In current industrial practice gas chromatographic analysis (glc) is used for quahty control. The impurities, mainly a small amount of water (by Kad-Fischer) and some organic trace constituents (by glc), are deterrnined quantitatively, and the balance to 100% is taken as the acetone content. Compliance to specified ranges of individual impurities can also be assured by this analysis. The gas chromatographic method is accurately correlated to any other tests specified for the assay of acetone in the product. Contract specification tests are performed on product to be shipped. Typical wet methods for the deterrnination of acetone are acidimetry (49), titration of the Hberated hydrochloric acid after treating the acetone with hydroxylamine hydrochloride and iodimetry (50), titrating the excess of iodine after treating the acetone with iodine and base (iodoform reaction). 

Reactions with Amines and Amides. Hydroxybenzaldehydes undergo the normal reactions with aUphatic and aromatic primary amines to form imines and Schiff bases reaction with hydroxylamine gives an oxime, reaction with hydrazines gives hydrazones, and reactions with semicarbazide give semicarbazones. The reaction of 4-hydroxybenzaldehyde with hydroxylamine hydrochloride is a convenient method for the preparation of 4-cyanophenol (52,53). 

A number of substances, such as the most commonly used sulfur dioxide, can reduce selenous acid solution to an elemental selenium precipitate. This precipitation separates the selenium from most elements and serves as a basis for gravimetry. In a solution containing both selenous and teUurous acids, the selenium may be quantitatively separated from the latter by performing the reduction in a solution which is 8 to 9.5 W with respect to hydrochloric acid. When selenic acid may also be present, the addition of hydroxylamine hydrochloride is recommended along with the sulfur dioxide. A simple method for the separation and deterrnination of selenium(IV) and molybdenum(VI) in mixtures, based on selective precipitation with potassium thiocarbonate, has been developed (69). 

The assay method involves the reaction of benzaldehyde with hydroxylamine hydrochloride in an alcohoHc solution. Benzaldehyde oxime, water, and hydrochloric acid are the products of the reaction. The hydrochloric acid formed is then titrated with standard caustic solution to determine the benzaldehyde assay. 

Cyclohexanone purity is most readily deteanined by gas-Hquid chromatography over DC-710 or carbowax 20M-on-chromosorb. Impurities such as cyclohexane, ben2ene, cyclohexanol, and phenol do not interfere. In the absence of other carbonyl compounds cyclohexanone may be deterrnined by treatment with hydroxylamine hydrochloride, which forms the oxime, as follows ... 

The chemical consequences of /3-protonation are illustrated further by the ring-opening reactions of furans with methanolic hydrogen chloride and of (V-substituted pyrroles with hydroxylamine hydrochloride (Scheme 11) (82CC800). 

The most useful general method for the C-acylation of pyrroles is the Vilsmeier-Haack procedure in which pyrrole is treated with the phosphoryl chloride complex (55a, b) of an AiA-dialkylamide (54). The intermediate imine salt (56) is hydrolyzed subsequently under mildly alkaline conditions to give the acylated pyrrole (57). On treatment of the imminium salt (56 R =H) with hydroxylamine hydrochloride and one equivalent of pyridine and heating in DMF, 2-cyanopyrrole (58) is formed (80CJC409). 

The isoxazoles (585) were formed regioselectively from the (dioxoalkyl)phosphonium salts (584) with hydroxylamine hydrochloride, the direction of cyclization being different from that of the nonphosphorus-containing 1,3-dioxo compound (see Chapter 4.16). Aqueous sodium hydroxide converted (585) into the isoxazole (586) and triphenylphosphine oxide. Treatment of (585) with n-butyllithium and an aldehyde gave the alkene (587). With hydrazine or phenylhydrazine analogous pyrazoles were formed (80CB2852). 

The reaction of the steroidal )3-ketoaldehyde (293) with hydroxylamine hydrochloride in acetic acid gave a mixture of the 3- and 5-substituted isoxazoles (294) and (295a). In sodium acetate buffer the reaction provided exclusively the 5-substituted isomer (29Sb) (66JOC3193). 

The reaction of )3-substituted vinyl ketones RCOCH=CHY (Y = halogen, OR or NR2) with hydroxylamine hydrochloride has been extensively investigated (63AHC(2)365, 62HC(l7)l). One would anticipate that replacement of hydroxylamine hydrochloride with hydroxylamine in these reactions would result in enhanced regiospecificity and increased... 

Since an electron-withdrawing group such as ethoxycarbonyl at the a-carbon atom enhanced the electrophilicity of the )3-carbon atom, the reaction of a-ethoxycarbonyl-)3-ethoxyvinyl ketones (298) with hydroxylamine hydrochloride gave solely 5-substituted isoxazole-4-carboxylates (299) (55JOC1342, 59YZ836). 

Alkyl-5-arylisoxazoles (303) were prepared by the regiospecific reaction of appropriate 1,3-diketones (302) (R = alkyl or perfluoroalkyl) with hydroxylamine hydrochloride in pyridine (79MI41601). 

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