"The chef commercial use of amines is as intermediates in the synthesis of medicines and fibers".
Amines constitute an important class of organic compound derived by replacing one or more hydrogen atoms of ammonia molecules by alkyl/aryl group(s). In nature, they occur among proteins, vitamins, alkaloids and hormones. Synthetic examples include polymers, dyestuffs and drugs. Two biologically active compounds, namely adrenaline and ephedrine, both containing secondary amino group, are used to increase blood pressure. Novocain, a synthetic amino compounds, is known anesthetic in dentistry. Benadryl, a well known antihistaminic drugs also contains tertiary amino group.
Quaternary ammonia salts are intermediates in the preparation of a variety of aromatic compounds including dyes.
I. AMINES
Amines can be considered as derivatives of ammonia, obtained by replacement of one, two or all the three hydrogen atoms by alkyl and/ or aryl group. CH3 一NH2, C6H5一NH2, CH3一NH一CH3, CH3, CH3一NノCH3 ∖CH3
Like ammonia, nitrogen atom of amines is trivalent and carries an unshared of electrons. Nitrogen orbitals in amines is pyramidal. Each of the three sp3 hybridized orbitals of nitrogen overlap with orbitals of nitrogen overlap with orbitals of hydrogen or carbon depending upon the composition of the amines. The forth orbital of nitrogen in all amines contains an unshared pair of electron. Due to the presence of unshared pair of electrons, the angle C-N-E, (where E is C or H) is less 109.5℃ for is 108℃ in case of trimethylamine.
