Amine sentence example
It has to some extent the character of a secondary amine; the hydrogen of the imino group can be replaced by potassium.
The tertiary amine is then distilled off, the residual products separated by filtration and finally hydrolysed by a caustic alkali.
The secondary amines may be of two types-namely,the purely aromatic amines, and the mixed secondary amines, which contain an aromatic residue and an alkyl group. The purely aromatic amines result upon heating the primary amines with their hydrochlorides, and, in some cases, by heating a phenol with a primary amine and anhydrous zinc chloride.
The mixed secondary amines are prepared by the action of alkyl iodides on the primary amines, or by heating salts of the primary amine with alcohols under pressure.
The simplest aromatic tertiary amine, triphenylamine, is prepared by the action of brombenzene on sodium diphenylamine (C. Heydrich, Ber., 1885, 18, p. 2156).Advertisement
Sodium in boiling amyl alcohol reduces it to aromatic tetrahydro-a-naphthylamine, a substance having the properties of an aromatic amine, for it can be diazotized and does not possess an ammoniacal smell.
They may be prepared by the reduction of nitro compounds in alkaline solution (using zinc dust and alkali, or a solution of an alkaline stannite as a reducing agent); by oxidation of hydrazo compounds; or by the coupling of a diazotized amine and any compound of a phenolic or aminic type, provided that there is a free para position in the amine or phenol.
Tschelinzeff (Ber., 1904, 37, p. 4534) showed that the ether may be replaced by benzene containing a small quantity of ether or anisole, or a few drops of a tertiary amine.
Chloroform may be readily detected by the production of an isonitrile when it is heated with alcoholic potash and a primary amine; thus with aniline, phenyl isocyanide (recognized by its nauseating smell) is produced, CHC13+C6H5NH2+3KHO=C6H5NC+3KC1+3H20.
In this process the amine salt is dissolved in absolute alcohol and diazotized by the addition of amyl nitrite; a crystalline precipitate of the diazonium salt is formed on standing, or on the addition of a small quantity of ether.Advertisement
The diazonium salts are characterized by their great reactivity and consequently are important reagents in synthetical processes, since by their agency the amino group in a primary amine may be exchanged for other elements or radicals.
Concentrated acids convert them into the isomeric nitro-amines, the - NO 2 group going into the nucleus in the orthoor paraposition to the amine nitrogen; this appears to indicate that the compounds are nitramines.
Hantzsch, Ber., This assumption also shows the relationship of the diazonium hydroxides to other quaternary ammonium compounds, for most of the quaternary ammonium hydroxides (except such as have the nitrogen atom attached to four saturated hydrocarbon radicals) are unstable, and readily pass over into compounds in which the hydroxyl group is no longer attached to the amine nitrogen; thus the syn-diazo hydroxides are to be regarded as pseudo-diazonium derivatives.
In the latter reaction it is assumed that the isodiazohydroxide first formed is immediately attacked by a second molecule of the amine.
It has also been shown that when different salts of the amine are used, their catalytic influence varies in amount and is almost proportional to their degree of ionization in aqueous solution.Advertisement
The attachment method comprises of a hydrophilic polymer network bound to the surface and contains amine or carboxylic reactive groups for end-point attachment.
Labeling in vitro is generally performed non-specifically using amine or thiol reactive reagents.
The document concludes that a large number of food products exceeded the government maximum permitted limit of histamine, a biogenic amine, a biogenic amine.
An aromatic primary amine is one in which the -NH 2 group is attached directly to a benzene ring.
In a tertiary amine there aren't any hydrogen atoms attached directly to the nitrogen.Advertisement
Figure 1. Spectral changes spaced a minute apart during enzyme catalysis in crystals of E. coli amine oxidase.
These enzymes represent a special class of the copper amine oxidases.
They are generally ambient cure when cured with an epoxy amine hardener.
An ammonium ion is formed, together with an amine.
That means that the primary amine is going to be a better nucleophile than ammonia is.Advertisement
Regional cerebral perfusion was also assessed using technetium-99m hexamethylpropylene amine oxime.
They develop from ' apud ' (amine precursor, uptake and decarboxylation) cells.
These enzymes catalyze many reactions such as carbon skeleton rearrangements or the removal of a methyl group from a tertiary amine.
When warmed with a solution of nitrous acid, they are converted into phenols; if, however, nitrous acid be added to an ice-cold solution of a primary amine in excess of mineral acid, a diazonium salt is formed (see Az o Compounds and DIAzO Compounds), or in absence of excess of acid, a diazoamine is produced.
They are crystalline solids, usually of a yellow colour, which do not unite with acids; they are readily converted into amino-azo compounds (see above) and are decomposed by the concentrated halogen acids, yielding haloid benzenes, nitrogen and an amine.Advertisement
Reinders (Ber., 1896, 29, p. 1369, 1899) have shown that the transformation is a monomolecular reaction, the velocity of transformation in moderately dilute solution being independent of the concentration, but proportional to the amount of the catalyst present (amine hydrochloride) and to the temperature.
When an imbalance occurs, the body produces histamine, a biogenic amine, which is released from the mast cells of the skin.