Sodium acetate nitrite

Attention has previously (see Diazonium Sails) been drawn to the fact that unless an excess of hydrochloric (or mineral) acid is used in the diazotisation process, coupling occurs between the diazonium salt and the amine to give diazoamino compounds. Thus phenyldiazonium chloride and aniline yield diazoaminobenzene. This substance may be conveniently prepared by dissolving two equivalents of aniline in three equivalents of hydrochloric acid, and adding one equivalent of sodium nitrite in aqueous solution followed by two equivalents of sodium acetate ... 

In a 250 ml. flask place 75 ml, of water, 24 g. (20 ml.) of concentrated hydrochloric acid and 14g. (13-7 ml.) of aniline. Shake vigorously (1) and then add 50 g. of crushed ice. Rim in a solution of 5-2 g. of so um nitrite in 12 ml. of water, with constant shaking, during a period of 5-10 minutes. Allow to stand with frequent shaking (1) for 15 minutes, and add a solution of 21 0 g. of crystallised sodium acetate in 40 ml. of water during 5 minutes. A yellow precipitate of diazoaminobenzene begins to form immediately allow to stand with frequent shaking for 45 minutes and do not allow the temperature to rise above 20° (add ice. 

Chlorodiphenyl. Diazotise 32 g. of o-chloroaniline (Section IV,34) in the presence of 40 ml. of concentrated hydrochloric acid and 22 -5 ml. of water in the usual manner (compare Section IV,61) with concentrated sodium nitrite solution. Transfer the cold, filtered diazonium solution to a 1 5 htre bolt-head flask surrounded by ice water, introduce 500 ml. of cold benzene, stir vigorously, and add a solution of 80 g. of sodium acetate trihydrate in 200 ml. of water dropwise, maintaining the temperature at 5-10°. Continue the stirring for 48 hours after the first 3 hours, allow the reaction to proceed at room temperature. Separate the benzene layer, wash it with water, and remove the benzene by distillation at atmospheric pressure distil the residue under reduced pressure and collect the 2-chlorodiphenyl at 150-155°/10 mm. The yield is 18 g. Recrystalliae from aqueous ethanol m.p. 34°. 

Diazoaminobenzene has been prepared by the action of sodium nitrite on aniline sulfate by the action of sodium nitrite on aniline hydrochloride by the action of sodium nitrite and sodium acetate on aniline hydrochloride by the action of ammonium nitrate and hydrogen sulfide on aniline hydrochloride in the presence of iron and by the action of amyl nitrite on aniline. ... 

Hydrogenation reduces the nitro group to amino which is then diazotized using sodium nitrite and tetrafluoroboric acid. The diazotized crown was not isolated but the aq. solution was treated directly with sodium acetate and bis(dibenzylideneacetone)-pal-ladium(O) in acetonitrile solution. Ethylene was then introduced to the autoclave and the solution was allowed to stir for 2 days. 4 -Vinylbenzo-15-crown-5 was isolated (30% from 4 -nitrobenzo-15-crown-5) as a colorless solid (mp 43.5—44.2°) °. The synthesis is illustrated in Eq. (3.16). 

The immediate outcome of the Hantzsch synthesis is the dihydropyridine which requires a subsequent oxidation step to generate the pyridine core. Classically, this has been accomplished with nitric acid. Alternative reagents include oxygen, sodium nitrite, ferric nitrate/cupric nitrate, bromine/sodium acetate, chromium trioxide, sulfur, potassium permanganate, chloranil, DDQ, Pd/C and DBU. More recently, ceric ammonium nitrate (CAN) has been found to be an efficient reagent to carry out this transformation. When 100 was treated with 2 equivalents of CAN in aqueous acetone, the reaction to 101 was complete in 10 minutes at room temperature and in excellent yield. 

Solid sodium nitrite (0.97 g) was added at room temperature with stirring over a period of one hour to a solution of 2-chloro-9-(2-hydroxyethoxymethyl)adenine (0.5 g) in glacial acetic acid (10 ml). The reaction mixture was stirred for an additional A A hours. The white solid was removed by filtration, washed with cold acetic acid and then well triturated with cold water to remove the sodium acetate present. The solid product was retained. The combined acetic acid filtrate and wash was evaporated at reduced pressure and 40°C bath temperature and the residual oil triturated with cold water. The resulting solid material was combined with the previously isolated solid and the combined solids dried and recrystallized from ethanol to give 2chloro-9-(2-hydroxyethoxymethyl)+iypoxanthine (0.25 g), MP>310°C. Elemental analysis and NMR spectrum were consistent with this structure. 

A solution of 140 g. (1 mole) of glycine ethyl ester hydrochloride 1 and 3 g. of sodium acetate in 150 ml. of water is added to the flask and cooled to 2° by means of an ice-salt bath. A cold solution of 80 g. (1.15 moles) of sodium nitrite in 100 ml. of water is added, and the mixture is stirred until the temperature has fallen to 0°. The temperature is maintained below 2°, and stirring is continued throughout all the following operations. To the cold mixture are added 80 ml. of cold, alcohol-free ethyl ether (Note 1) and 3 ml. of cold 10% sulfuric acid. After 5 minutes, the reaction mixture is blown over into the 1-1. separatory funnel by application of air pressure. The lower aqueous layer is quickly sucked back into the reaction flask. The ether layer is removed and immediately washed with 50 ml. of cold 10% sodium carbonate solution. This ether solution should be neutral to moist lilmus paper if not, the washing with sodium carbonate is repeated. The ether solution is finally dried over 10 g. of anhydrous sodium sulfate. 

In 1904 Bally obtained a bluish violet solid by alkali fusion of benzanthrone at approximately 220 °C. Two isomeric compounds were isolated by vatting the reaction mixture and filtering off a sparingly soluble sodium salt. Oxidation of the filtrate gave a blue vat dye, violanthrone (6.75 Cl Vat Blue 20), as the main component. The less soluble residue similarly afforded a violet product, isoviolanthrone (6.76 Cl Vat Violet 10). The formation of isoviolanthrone can be suppressed by carrying out the fusion in a solvent such as naphthalene or a polyethylene glycol in the presence of sodium acetate and sodium nitrite. Dyes of this type are often referred to as dibenzanthrones. 

For preparative diazotisations it is important to use a sufficient excess of acid and to keep the temperature down. Two moles of acid are required for each mole of amine, one for salt formation and one for liberating the nitrous acid from the nitrite. As a rule 2-5-3-0 moles are used. The excess is required to prevent condensation of the diazonium salt with unchanged base to diazoamino-compound such condensations take place in a faintly acid medium. The test for unchanged amine, accordingly, consists in buffering the free mineral acid with sodium acetate, and so providing a solution faintly acid with acetic acid, under which conditions the diazoamino-compound is formed. The latter is decomposed by mineral acids into diazonium salt and amine salt, e.g. 

Congo Red.1—Dissolve 4-6 g. of benzidine in a hot mixture of 12 c.c. of concentrated hydrochloric acid and 100 c.c. of water, add 150 c.c. more water, cool the clear solution to 2°-3°, and diazotise with 3-6 g. of sodium nitrite in 20 c.c. of water, added within the space of one minute. Leave the tetrazo -solution for five minutes and then pour it with stirring into a solution of 16 g. of sodium naph-thionate and 20 g. of crystallised sodium acetate in 250 c.c. of water. When a sample of the liquid, on warming with hydrochloric acid, no longer evolves nitrogen, dissolve the blue-black precipitate of the dye-acid by warming with sodium carbonate and so produce the red sodium salt filter and salt out the product from the filtrate with common salt (not too much). Collect the precipitate at the pump and wash with brine. The blue acid can be precipitated from the solution of the sodium salt with hydrochloric acid. 

Diazoaminobenzene and p-Aminoazobenzene.—Diazotise 9-3 g. of aniline to the extent of one half under the usual conditions with half the amount of nitrite (3-8 g.) and add to the solution, with stirring, a solution of 25 g. of sodium acetate in 100 c.c. of water. 

Lithium carbonate, 0533 Lithium dithionite, 4687 Magnesium carbonate hydroxide, 0534 Magnesium nitrate, 4693 Magnesium nitrite, 4692 Magnesium sulfate, 4696 Potassium carbonate, 0531 Potassium nitrite, 4649 Silver hyponitrite, 0031 Sodium acetate, 0779 Sodium carbonate, 0552 Sodium disulfite, 4808 Sodium dithionite, 4807 Sodium hydrogen carbonate, 0390 Sodium hydrogen sulfate, 4446 Sodium metasilicate, 4805 Sodium nitrite, 4720 Sodium sulfate, 4806 Sodium tetraborate, 0185 Sodium thiosulfate, 4804... 

Ethyl-a-Keto-y-dimethylaminobutyrate p-Acetylphenylhydrazone. (JMC, 7, 144 (1966)). 40 g of p-aminoacetophenone in 250 ml of water and 143 ml of coned hydrochloric acid is diazotized at 0-5° with 21 g of sodium nitrite in 200 ml of water. To the resulting solution is added 60.3 g of ethyl a-(2-dimethylaminoethyl)aceto-acetate followed by 63 g of sodium acetate. Raise the pH to 6.5 and maintain with the addition of 3 N NaOH (also use the 3 N for the initial raise to 6.5). Stir, with external cooling for 2 hours, make basic, and extract with three 400 ml portions of ehloroform. Combine the extracts and dry over sodium sulphate, eoneentrate in vacuo. Crystallize the residue with a mixture of benzene-petroleum ether, after purification with charcoal, to get 65 g. Crystallize two more times to get a melting point of 84-85°. 

Plumes from biomass burning can also have unique signatures. For example, organics, ammonium, potassium, sodium, nitrate, nitrite, sulfate, chloride, phosphate, elemental carbon, and the anions of organic acids (formate, acetate, oxalate, etc.) have all been measured in particles in the plumes from burning vegetation (e.g., see Cofer et al., 1988 Andreae et al., 1988 and Artaxo et al., 1994). 

The amine (0.1 mole) is dissolved in a buffered (pH 4-5) solution of 500 ml of 60 % aqueous acetic acid and 68 gm of sodium acetate. The reaction mixture is warmed to 90°C. Then 69 gm (1.0 mole) of sodium nitrite dissolved in 100 ml of water is added dropwise over a 45 min period while heating at 90°C is continued. After the addition, the reaction mixture is heated for 2 hr, cooled, poured into 200 ml of cold water, and extracted three times with 200 ml portions of ether. The ether was washed with 10 % potassium carbonate solution until basic, then with saturated sodium chloride solution, dried, stripped, and distilled to obtain the products shown in the table. 

Deamination of e,nwith sodium nitrite in acetic acid/sodium acetate gave a mixture of compounds from which, after reduction of the crude mixture with lithium aluminum hydride, was isolated bicyclo[3.1.1]heptanediol 23 in 20% yield by chromatography.88,89... 

Reaction of 2,3-diamino-l 17/-pyrido[2,l -h]quinazolin-l 1-ones (162) with sodium nitrite in aqueous acetic acid at 40°C for 1 h, or with diphenylni-trosamine in acetic acid in the presence of sodium acetate at 75-85°C gave linear tetracyclic derivatives (163) (84GEP3300477). 

The best method of preparation, however, is as follows 2 9 1 grams of aniline in dilute sulphuric acid (1 4) are diazotised at 3° C. with 9 5 grams of sodium nitrite and the solution, made neutral to Congo paper with sodium acetate, is added to a cold aqueous solution of 22 grams of potassium selenocyanate. After fifteen hours steam distillation gives a pale yellow oil, which, when dried over calcium chloride, boils at 134° C. at 10 mm. and at about 250° C. with decomposition at ordinary pressures. The yield is about 50 per cent. When nitrated at -5° C. with nitric acid (density 1 5), p-nitrophenyl selenocyanate and a very small amount of o-nitrophenyl selenocyanate are obtained. p-Chlorophenyl selenocyanate,... 

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