141-52-6 sodium ethylate

The thiazolium is not acidic enough for observing directly solvation of the molecule (or an hydrolysis and subsequent cleavage of the ring) (24) without adding a base, as it is the case for benzoxazolium or benzothiazolium. With the same dilution (10 mole liter ), it is necessary to add sodium ethylate to the solution of 2-methyl-4.5-diphenylthiazolium to observe the equilibrium described above. A new band appears in the UV spectrum at 320 nm that is attributed to the ethoxy derivative by analogy to what has been observed with other benzothiazoliums (26),... 

Salts are formed as with oxygen-containing compounds. For example, C2H5 — S—Na is named either sodium ethanethiolate or sodium ethyl sulfide. If mercapto- has been used as a prefix, the salt is named by use of the prefix sulfido- for —S . 

Sodium ethyl thiosulfate [26264-37-9] is also known as Bunte s salt after the name of its discoverer. Bunte salts may be thought of as esters of thiosulfuric acid (94—96). In essentially all of their chemical reactions, the cleavage is between the divalent and hexavalent sulfur atom. For example, acid hydrolysis produces a thiol and the acid sulfate ... 

Fig. 1. Solubihty of some commercial xanthates. (—), Sodium isobutyl xanthate (-), sodium ethyl xanthate (—...

Further hydrolysis of the carbon disulfide and the trithiocarbonate produces hydrogen sulfide, etc (33). In another study of the decomposition of sodium ethyl xanthate [140-90-9] in flotation solutions, eleven components of breakdown were studied. The dependence of concentration of those components vs time was examined by solving a set of differential equations (34). 

Where no water is present, very pure xanthates form (65). Ethanol reacts slowly with sodium trithiocarbonate to produce sodium ethyl xanthate... 

The most important hazard ia the manufacturiag of xanthates is the use of carbon disulfide (qv) because of its low flash poiat, ignition temperature, and its toxicity. A report on the manufacture of sodium ethyl xanthate at Keimecott Nevada Mines Division discusses the various safety problems and the design of a faciUty (81). A plant layout and a description of the reagent preparations are also given. 

Because of hydrate formation, the sodium salts tend to be difficult to dry. Excess water over that of hydration is beheved to accelerate the decomposition of the xanthate salts. The effect of heat on the dryiag of sodium ethyl xanthate at 50°C has been studied (84) ... 

Xanthate dmms should be kept as cool and dry as possible. Protection from moisture is the most important factor. A combination of moisture and hot weather causes sodium ethyl xanthate to ignite spontaneously (14). 

Ethyl acetoacetate has been prepared from ethyl acetate by the action of sodium/ sodium ethylate/ sodamide/ and calcium. ... 

Ethyl acetopyruvate has been prepared only by the condensation of ethyl oxalate and acetone in the presence of sodium ethylated The method given above is based on that of Claisen and Stylosd... 

About half of the sodium ethylate solution is poured into a 3-]. round-bottomed, three-necked flask provided with a liquid-sealed stirrer and a reflux condenser the other half is kept warm by a small flame. The first half of the solution is allowed to... 

The most convenient laboratory method for the preparation of 2,4-dimethyl-5-carbethoxypyrrole is that given above. A cheaper method of obtaining large quantities consists in the partial hydrolysis of 2,4-dimethyl-3,5-dicarbethoxypyrrole with sulfuric acid, followed by decarboxylation. The ester has been obtained also by the alcoholysis of 5-trichloroaceto-2,4-dimethyl-pyrrole in the presence of sodium ethylate. The free acid has been obtained fronii-[2,4-dimethylpyrrole-5]-2,4-dimethylpyrrole-5-carboxylic acid and from 2,4-dimethylpyrrole-5-aldehyde. ... 

Suitable organic solvents, such as ether, benzene, naphtha and the like, are more soluble than in water. This makes it possible to separate them from other substances which may accompany them in the water solution but which are not soluble in the solvents employed. Hence, one application of solvent extraction is the analytical determination of unsaponifiable oils and waxes in admixture with fatty material by submitting the mixture to vigorous saponification with alcoholic potash or, if necessary, sodium ethylate, and to dilute the product with water and extract with petroleum ether. The soaps remain in the aqueous solution while the unsaponifiable oils and waxes dissolved in the ether. The addition of a salt to an aqueous solution prior to extraction is sometimes practiced in some processes. In older processes, SOj is employed in the separation of aromatic and highly saturated hydrocarbons, taking advantage of the much greater solubility of the solubility of the aromatics and... 

The formation of ethyl acetoacetate occurs, according- to Claisen, in four steps. The presence of a small quantity of alcohol gives lise to sodium ethylate, which forms an additive compound with ethyl acetate. The latter unites with a second molecule of ethyl acetate yielding the sodium salt of ethyl acetoacetate, and splitting off alcohol, which reacts with fresh metallic sodium. The sodium salt on acidifying passes into the tautomeric (ketonic) form of acetoacetic ester. 

Ethyl Acetoacetate. -The e. planation of the manner in which this substance is produced has been given in the account of the preparation. The result was anived at, not by the iscila-tion of the intermediate compound formed by the union of ethyl acetate with sodium ethylate, but by analogy with the behaviour of benzoic methyl ester with sodium benzylate, which gave the same additive product as that obtained by combining benzoic benzyl ester with sodium methylate, showing that such combinations could occur,... 

Also by the fact that sodium only attacks ethyl acetate in presence of ethyl alcohol, although the quantity of the latter may be very minute. Similar reactions have been effected with either metallic sodium or sodium ethylate by Claisen,... 

For unsubstitUted or lower alkylated dioxotriazines, it is advantageous to cyclize semicarbazones by sodium ethylate in ethylene glycol as described by Chang and XJlbricht. In this reaction 6-aza-uracil is obtained in 66% yield. The procedure was used for the preparation of labeled 6-azauracil ° and later for the synthesis of a number of 6-alkyl derivatives including 6-azathymine. °... 

The reaction of diacetylene or its monosubstituted homologs with guanidine in the presence of an equimolar amount of sodium ethylate (80°C, EtOH, 14 h) leads to 2-amino-4-alkylpyrimidines (33) (70ZOR1347 71ZOR14). Their structures were proved by comparison of their properties (as well as those of their picrates) with those of authentic samples obtained by independent synthesis. 

The methyl group position was fixed both by cleavage of the isoxazole ring with sodium ethylate and by isolation of the cyanacetone sodium salt 125. The reaction of this salt with phenylhydrazine resulted in the phenylhydrazone of cyanacetone (126) (69ZOR1179). 

This group of reactions has already been reviewed by Quilico and Barnes. However, the important data recently published make it advisable to reassess the subject. In 1891 Claisen first gave an example of the cleavage of the isoxazole ring he treated 5-phenylisoxazole with dilute sodium hydroxide or sodium ethylate at room temperature,the reaction involving the cleavage of the 0—N bond to yield a y8-ketonitrile (106). 

Further investigation of the action of sodium ethylate on isoxazole showed that under the same conditions the ring of isoxazole itself is cleaved as well as that of 4- and 5-monosubstituted and 4,5-disub-stituted isoxazoles, that is to say, in all isoxazoles unsubstituted at the 3-position, i.e. 107— 108. 

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