الفهرس 
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Abstract
A- Preparation Of Different Amino Organic Compounds. 1- Introduction.
Amines can be considered to be derived from ammonia
by replacement of one, two or three hydrogens by alkyl or aryl groups. The number of hydrogens that have been rep¬laced serves as the basis for a system for classifying amines.
The nitrogen of amines, like that of amnlonia, is a Lewis base, since the nitrogen has a pair of electrons that can be shared with another atom. This basic property of the arrlines is their most important characteristic. They form salts with both inorganic and organic acids. It is also possible to prepare compounds having four similar or different groups attached to the nitrogen, and thus obtain a quanternary ammonium salt.
As their names imply, the quaternary ammonimu salts
are ionic materials with properties that are characteristic of ionic materials. The nitrogen is bonded by covalent bonds to four carbons and by an ionic bond to an anion. These compounds are not amines, as the nitrogen does not have a pair of electrons that can be shared with another atom.
2
Amines may be prepared by a wide variety of methods, everyone completely different from the other.,
Different Methods for the ~reparation of Amino Organic
Oompounds :
a - .. Amination of alkyl and aryl halides :
Hofmann discovered that alkyl groups can be intro-
duced directly into ar~llonia by interaction with an alkyl
halide and subsequent treatment with alkali. The reaction
is general, but it has the disadvantage that higher substi-
tution is ineviatable.
+ - NaOH
CH) CH2 Br + NH) ---,.. CH) CH2NH3 Br tCH3 CH2 NH2o. 0 (1)
Thus in the reaction of ethyl bromide with ammonia,
the ethyl 8liilllonium bromide as it is formed enters into equi-
librium with a@nonia still present with liberation of ethyla-
mine. The primary amine then competes with ammonia for the
alkyl halide and yields SOIYle of the secondary 8nine salt 0
However, a simple ~xpedient for suppression of the unwanted secondary amine is to use so large excess of ammonia