Fusion of the sodium salt

By fusion of the sodium salt vith caustic soda and potassium chlorate, the hydio yl yioups enter the u and jS position. The constitution of ali/aiin is theiefore... 

The method described is essentially that of La Forge.2 Nicotinonitrile has also been prepared from nicotinic acid by heating with ammonium acetate and acetic acid,3 from 3-pyridinesulfonic acid by fusion of the sodium salt with sodium cyanide,4 and from 3-bromopyridine and cuprous cyanide.6... 

A number of annelated 1,3,4,6-thiatriazepines (613) have been prepared by the reactions of the sodium salts of cyclic thioureas with dichlorodiazabutadienes (612). Acyclic thioureas take an alternative reaction path via the elimination of a carbodiimide to give only 2,5-diphenyl-l,3,4-thiadiazole (80CC156). An X-ray structure determination on (613 n = 2) shows that the seven-membered ring has the expected boat conformation and that ring fusion does not appear to strain the five-membered ring <81AX(B)486>. 

The choline salts of naproxen and tolmetin yielded marked solubility enhancements, even over that of the sodium salts. The aqueous solubility of the choline salt of naproxen was 6700 times the solubility of naproxen and almost twice that of naproxen sodium. The choline salt of tolmetin was almost 8000 times as soluble as the parent drug and almost 5 times as soluble as its sodium salt (Murti, 1993) (Cheenu dissertation, our unpublished results). Table 15.2 shows that the melting points and enthalpies of fusion are both affected by the formation of the choline salt, and in fact, the choline salt proved to be more thermally stable. 

The decarboxylation of simple aliphatic acids by fusion of their sodium salts with sodium hydroxide does not give pure hydrocarbons. By heating the barium salts of 1-phenylcycloalkane-l-carboxylic acids with dry sodium methoxide, 1-phenylcycloalkanes are obtained in 6-64% yields, the yield increasing with the size of the alicyclic ring. The coupling of the... 

Fusion of the sodium or potassium salt of 4-(a-hydroxyalkylidene)-2-oxazoline-5-ones (90) leads, by rearrangement, to oxazole-4-carboxylic acids (91) which can easily be decarboxylated to the corresponding oxazoles.2 4 This rearrangement occurs also in alkali, and a 14C tracer... 

A further point of interest concerns the reaction of the iminium salts 118 and 120 with borohydride (65). The reduction of 118 or 120 with sodium borohydride gave an identical product mixture in which the major components were 6-0-methylmesembranol (121) and 6 -0-methyl-7a-epimesem-branol (122) in 78% and 16% yields, respectively (see Scheme 32). Two minor components representing less than 6% of the total products were identified as mesembrane and its C-7a epimer 123. While the structures of the compounds with a trans ring fusion rested on spectral evidence, the identity of 6-0-methylmesembranol was established by its synthesis from mesembranol by selective O-methylation of the sodium salt with methyl-p-toluenesulfonate, while that of c -mesembrane was identified by comparison with an authentic sample. 

Naphthalenesulfonic Acid. The sulfonation of naphthalene with excess 96 wt % sulfuric acid at < 80°C gives > 85 wt % 1-naphthalenesulfonic acid (a-acid) the balance is mainly the 2-isomer (P-acid). An older German commercial process is based on the reaction of naphthalene with 96 wt % sulfuric acid at 20—50°C (13). The product can be used unpurifted to make dyestuff intermediates by nitration or can be sulfonated further. The sodium salt of 1-naphthalenesulfonic acid is required, for example, for the conversion of 1-naphthalenol (1-naphthol) by caustic fusion. In this case, the excess sulfuric acid first is separated by the addition of lime and is filtered to remove the insoluble calcium sulfate the filtrate is treated with sodium carbonate to precipitate calcium carbonate and leave the sodium l-naphthalenesulfonate/7J(9-/4-J7 in solution. The dry salt then is recovered, typically, by spray-drying the solution. 

In the manufacture of 2-naphthalenol, 2-naphthalenesulfonic acid must be converted to its sodium salt this can be done by adding sodium chloride to the acid, and by neutralizing with aqueous sodium hydroxide or neutralizing with the sodium sulfite by-product obtained in the caustic fusion of the sulfonate. The cmde sulfonation product, without isolation or purification of 2-naphthalenesulfonic acid, is used to make 1,6-, 2,6-, and 2,7-naphthalenedisulfonic acids and 1,3,6-naphthalenetrisulfonic acid by further sulfonation. By nitration, 5- and 8-nitro-2-naphthalenesulfonic acids, [89-69-1] and [117-41-9] respectively, are obtained, which are intermediates for Cleve s acid. All are dye intermediates. The cmde sulfonation product can be condensed with formaldehyde or alcohols or olefins to make valuable wetting, dispersing, and tanning agents. 

H-acid, l-hydroxy-3,6,8-ttisulfonic acid, which is one of the most important letter acids, is prepared as naphthalene is sulfonated with sulfuric acid to ttisulfonic acid. The product is then nitrated and neutralized with lime to produce the calcium salt of l-nitronaphthalene-3,6,8-ttisulfonic acid, which is then reduced to T-acid (Koch acid) with Fe and HCl modem processes use continuous catalytical hydrogenation with Ni catalyst. Hydrogenation has been performed in aqueous medium in the presence of Raney nickel or Raney Ni—Fe catalyst with a low catalyst consumption and better yield (51). Fusion of the T-acid with sodium hydroxide and neutralization with sulfuric acid yields H-acid. Azo dyes such as Direct Blue 15 [2429-74-5] (17) and Acid... 

MetaHic potassium and potassium—sodium alloys are made by the reaction of sodium with fused KCl (8,98) or KOH (8,15). Calcium metal and calcium hydride are prepared by the reduction of granular calcium chloride with sodium or sodium and hydrogen, respectively, at temperatures below the fusion point of the resulting salt mixtures (120,121). 

For direct precipitation of vanadium from the salt-roast leach Hquor, acidulation to ca pH 1 without the addition of ammonia salts yields an impure vanadic acid when ammonium salts are added, ammonium polyvanadate precipitates. The impure vanadic acid ordinarily is redissolved in sodium carbonate solution, and ammonium metavanadate precipitates upon addition of ammonium salts. Fusion of the directly precipitated ammonium salts can yield high purity V20 for the chemical industry. Amine solvent extraction is sometimes used to recover 1—3 g/L of residual V20 from the directly precipitated tail Hquors. 

This procedure is particularly time-saving when scrap platinum or spent catalyst is used for the preparation of platinum oxide, for after conversion to chloroplatinic acid a purification is conveniently effected by precipitating the ammonium salt, and the direct fusion of this with sodium nitrate eliminates the tedious process of reconversion to chloroplatinic acid. Furthermore ammonium chloroplatinate is not hygroscopic and can he accurately weighed. The amount of catalyst obtained is almost exactly half the weight of the ammonium salt employed. 

Previously, phenol was produced from benzene by sulfonation followed by caustic fusion to sodium phenate. Phenol is released from the sodium salt of phenol by the action of carbon dioxide or sulfur dioxide. 

The fusion of powdered potassium hydroxide and carbazole together at 220-260°C has been often used for the preparation of the potassium salt of carbazole, the salt then being utilized in hydrocarbon solvent powdered potassium hydroxide was shown " to be better for this purpose than strong aqueous sodium hydroxide. Many 9-alkylations have been conducted in this way including preparations of dicarbazol-9-ylalkanes [29 R = (CH2)3 g-carbazol-9-yl] (using the corresponding dihalides), 9-(2,3-epoxyprop-l-yl) O / ... 

E. Mitscherlich 20 found that an intimate mixture of potassium and sodium carbonates fuses at a lower temp, than either salt alone, and E. Stolba found that at ordinary temp, the sp1 gr. of the fused mass was 2 53-2 56. H. le Chatelier obtained the V-eutectic at 6 J0° with 48 5 per cent. Na2C03 with no sign of the formation of a compound of the two salts at fusion temp. These facts of course do not prove the formation of a chemical... 

Potassium Niobates are generally produced by fusion of the metal or the pentoxide with potassium hydroxide, potassium carbonate, or potassium nitrate,3 or by the action of solutions of caustic potash or of potassium carbonate on niobic acid.4 They are among the most stable of the niobates their solutions can be boiled without precipitation of the acid. On being treated with sodium salts, for example sodium chloride, sodium niobates are precipitated. 

Reaction XXXIX. Fusion of the Salts of Aromatic Sulphonic Adds with Sodium Cyanide or with Sodium Formate.—These are important reactions which result in the formation of nitriles and carboxylic acids. 

Isolation of Sodium Salt.—The sodium salt is isolated when fusion with caustic soda is anticipated. To the filtrate containing the Ca salt in solution, sodium carbonate is added until no more CaC03 is precipitated (test). The CaC03 is filtered off and washed, and the filtrate evaporated, yielding the Na salt. 

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