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Amines

The amines are organic compounds containing nitrogen; compounds can be considered ammonia derived by substitution of one, two or three hydrogen atoms with alkyl groups or aryls.
Based on the number of hydrogen replaced, the amines are classified into primary, secondary or tertiary. If there is a hydrogen atom replaced, the amine is defined as primary, with two hydrogen atoms replaced the amine is known as secondary, with three hydrogen atoms replaced the amine is known as tertiary. Then there are ammonium salts, containing a

nitrogen atom having positive charge, linked to four alkyl or aryls groups: they are also defined quaternary amines.

As in the ammonia, the nitrogen atom of the amines has pyramidal geometry (tetrahedra) and a triangular base and such as ammonia, the amines are basic. Amines with more than three carbon atoms are supposed to be chiral, but, due to the pyramid inversion (the molecule is reversed quickly in solution), the racemic mixtures are not solvable. The doublet electronic not shared of nitrogen atom can be transferred to an acid species and, because of the increased electron inductive effect repulsore which is subject to nitrogen, the order of increasing basicity follows aliphatic amines from primary to secondary to higher levels of basicity of the tertiary. Aromatic amines have lower basicity due to the resonance that acts relocate the place on the electronic doublet aromatic making it more acidic ammonium ion and the ring more basic. Amines form easily soluble salts with mineral acids (hydrochloric acid or sulfuric acid) and are often marketed in this form.

The amines generally have boiling points higher than alkanes with similar molecular weight, because of hydrogen bonds in the molecules that they exchange among themselves. The intensity of the link, however, is less strong than observed in similar oxygenates (alcohols, carboxylic acids). Moreover, the possibility of forming hydrogen bonds makes the amines soluble in polar solvents, such as water, when the aliphatic or aromatic chain is short enough not to prevent it.
Molecules that contain different amino groups are called polyamines, among them the most important are the spermina and spermidina. The amines are generally toxic and aromatic amines compounds are suspected or detected carcinogenic. Some of the amines that are formed from products of decomposition of animals organic materials are putrescine, cadaverine and methylamine. Many amines are synthesized by use of plant organisms that form complex molecules called alkaloids such as morphine, quinine (used against malaria), nicotine (an essential component of cigarettes). Other compounds such as p-amino benzoic acid inhibit bacterial growth without affecting human cells.

On the toxicity and carcinogenicity of the so-called aromatic amines, there is a case for divided groups-group 1-2-3 with references toxicity not yet defined as to the 3rd group which is still being testing/mapping. This phase is in place since the 80th.
IUPAC nomenclature may consider the amine group or a substituent – in this case is identified by the prefix amino– or as the main group of the molecule – whose name in this case has the suffix-amine. The Chemical Abstract considered amines as alcanammine and aromatic amine as a result of benzenammina, more generally, the aromatic amines are considered derivatives by aniline.
The amines can be synthesized by treating ammonia with an alkyl halide (which is called ammonolisi of halides), then with a strong base like sodium hydroxide.
This reaction suggests the natural tendency of amines to interact with the alkyl halide (similar to the trend of ammonia) leads to the formation of secondary and tertiary amines, where the last can in turn attack the alkyl halide to form a quaternary ammonium salt.

A specific method of preparation for primary amines is a synthesis of Gabriel. This method obviously hindered the formation of classes of undesirable amines. This synthesis starts from an imides, usually the phthalimide, which is converted into a salt by reaction with potassium hydroxide (KOH) and can react with an alkyl halide to give a N-substituted imides, which on hydrolysis free phthalic acid and a primary amine. Are formed only primary amines because the salt nitrogen atom of phthalimide may bind only one alkyl group, which can obtain only the primary amine. Phthalic acid can be used to heating and subsequent dehydration, to regenerate the phthalic anhydride and continue the synthesis.

 

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Talloil

Talloil (derived from the Swedish tall√∂l, as “pine oil”) – Mix of resin acids ( abietic acid type), fatty acids (mainly olic and linoleic), alcohols, hydrocarbons and other organic substances, obtained acidified the part that floats on residual lyes from extraction of cellulose from resinous wood. Dark in color and odor typically is used, after purification and refining, on minerals flotation, to prepare bitumen emulsions, detergents, adhesives, plasticizers, lubricants and as a source of fatty acids and resins.