Amines, simple

In Section 3.4 we discussed the problem of reversibility of diazotization of aromatic and heteroaromatic amines. Simple stoichiometric considerations indicate that the reverse reaction (ArNJ -> ArNH2) may take place under strongly acidic conditions. Experimentally the reverse reaction was found only with heteroaromatic diazonium salts (Kavalek et al., 1989). Reaction conditions of hydroxy-de-diazonia-tion are comparable to those used for the reverse reactions of diazotization (e.g., 10 m H2S04, but at 0°C for the formation of 2-amino-5-phenyl-l,3,4-thiadiazol from the corresponding diazonium salt, Kavalek et al., 1979). So far as we know, however, amines have never been detected in aromatic hydroxy-de-diazoniations, not even in small amounts. 

The tautomerism of a methyl group a or 7 to a ring nitrogen (86 87) is still less favorable than that of the amine simple valence and electronegativity considerations of the type employed above suggest much reduced aromaticity associated with the methylene tautomer (87). These tautomers are therefore present to only a very small extent at equilibrium. 

Aromatic and aliphatic amines Simple aliphatic primary, secondary and tertiary amines have toxic vapours, e.g. diisopropylamine (RL 5 p.p.m., 20mgm-3),... 

It will be noted that some drugs in Table 8-4 are tertiary not quaternary amines. Simple tertiary amines would not be expected to have cholinergic activity, even though they would be considerably ionized at physiological pH. If other components of such a molecule contained interactive capability to bind with a receptor it might function as an agonist. 

Reaction of carboxylic esters with hydrazines is generally easier than that with amines. Simple aliphatic esters often give the corresponding hydrazide exothermally at room temperature, though it is advisable to warm the mixture on the water-bath for a short time thereafter. In such reactions the formation of 1,2-diacylated hydrazines rarely proves troublesome although it is a frequent side reaction when acid chlorides or anhydrides are used. The following details exemplify the technique ... 

Anti-stripping agents are chemical substances that have a similar composition to emulsifiers and are divided into (a) anionic type, such as organic acids (creosote) and fatty acids (oleic acid, stearic acid, pine pitch, etc.), and (b) cationic type, such as amines (simple amines, diamines, tertiary amines, polyamines and imidazolines) and salts of quaternary ammonium. 

Simple Amines, Simple Aromatic and Pyridine Alkaloids... 

E. P. Plueddemann 1) The adhesion of Hypalon to aminosilane-treated fillers is, as suggested by Mr. Schmukler, most probably through reaction of -S02CI groups with the amine. Simple amine-... 

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