Salts, fused, reactions carboxylic acids

An even simpler route to the fused-ring 1,3-dithiolium salts is by condensation of 203 with aromatic and even aliphatic carboxylic acids.131,13 > 137 The reaction, which is generally carried out in phosphorus oxychloride, proceeds rapidly and always in good yield. The parent member of this series of benzo-l,3-dithiolium salts is obtained in 80-90% yield when the acid used is formic acid (Table... 

Reactive halogen compounds such as benzyl chloride, 2-thenyl chloride, 2-bromoacetylthiophene, (C HjS)COCH,Br , and 2-chloromethyl-thianaphthene (C,H5S)CHjCl are readily converted to esters by treatment with the sodium salts of carboxylic acids. A small amount of tri-ethylamine has proved to be an effective catalyst. Acetates are oftentimes made by heating halides with fused sodium acetate in glacial acetic acid, e.g., p-ethylbenzyl acetate (93%). The reaction is of little value for the preparation of simple aliphatic esters. Secondary and tertiary halides give increasing amounts of olefin by dehydro-halogenation. 

Thiete structures have been suggested as fragmentation products in the mass spectra of a thietane fused to a 3-lactam, an ortho disulfide of a thiolbenzoate ester, -propanethiol, thiirane carboxylic acid esters, isothiazoles, thiazoles, 1,3-dithiole 2-thiones, 1,3-dithiolene-2-ones, S-ethyl thio-benzoate, and thianaphthene sulfones. Tetramethylthiete may have been formed on thermolysis of the p-toluenesulfonyl-hydrazone of 2,2,4,4-tetramethyl-3-thietanone. " Thiete 2-thione may be an intermediate in the decomposition of 1,2-ditholium salts by the action of bases. " 2,2-Diphenyl-2H-thiete is suggested as an intermediate in the reaction of diphenyldiazomethane with 1,2,3-benzo-thiadiazole which yields 9-phenylthioxanthene and three other products. ... 

Pyridine is a tertiary amine its aqueous solution shows an alkaline reaction and precipitates the hydroxides of metals, some of which are soluble in an excess of the amine. Salts of pyridine like those of other amines form characteristic double salts with metallic halides. The ferrocyanide of pyridine and the addition-product of pyridine and mercuric chloride are difficultly soluble in water these compounds are used in the purification of the base. Pyridine is a very stable compound it can be heated with nitric acid or chromic acid without undergoing change but at 330° it is converted by a mixture of nitric acid and fuming sulphuric acid into nitropyridine, a colorless compound that melts at 41° and boils at 216°. At a high temperature pyridine is converted into a sulphonic acid by sulphuric acid. Chlorine and bromine form addition-products, e.g., C5H5N.CI2, at the ordinary temperature when these are heated to above 200°, substitution-products are formed. The hydroxyl derivative of pyridine is made by fusing the sulphonic acid with sodium hydroxide it resembles phenol in chemical properties. The three possible carboxyl derivatives of pyridine are known. The a-acid is called picolinic acid, the jS-acid nicotinic acid (664), and the 7-acid isonicotinic acid. 

Salicyloylguanidines 19, 459 Salts, exclusive of — 19, 739 —, fused, reactions in — 18, 942 —, inner s. Betaines, Mercury-carboxylic acid inner salts —, organic... 

Complexation by the amino acids prior to polymerization alters the kinetics of chain propagation, which is consistent with the presumed catalytic role of the metal in these reactions (57), but amino acid salt formation has further implications from the standpoint of chemical evolution the polymerizations may be performed at temperatures that more closely resemble those found on the Earth s surface. Amino acids form salts with carboxylic acids (e.g. formic and acetic), and these salts tend to melt at lower temperatures than the corresponding amino acid. For example, a nrixtuie of the formate salts of glutamic acid and glycine (analogous to the first Harada-Fox melt, reference 27) fuses at 150°C, and the yield of polymer after foiu hours exceeds the typical yield obtained with the corresponding melt of amino acids. This trend towards lower melting points continues as one increases the number of amino acids in the mixture as a mixture of their formate salt, the Fox-Harada mixture of 16 amino acids (cf. reference 28) is a viscous paste at room temperature. The formation of peptides and ultimately precipitation of macromolecules from a concentrated aqueous solution of amino acid salts can be effected at 50°C. 

In another type of reaction, halogenated hydrocarbons react with alkali metals to produce alkanes of double the carbon content (equation 26.2). Finally, alkali metal salts of carboxylic acids can be fused with alkali metal hydroxides. Sodium carbonate and an alkane with one carbon fewer than the metal carboxylate are formed (equation 26.3). 

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