설명(영) |
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The organic substitution compounds of ammonia, NH3, are called Amines. In primary amines the amino group is singly substituted, i.e., RNH2; in secondary amines, the amino group carries two organic substituents, i.e. RR'NH; in tertiary amines, three organic radicals are attached to the amino nitrogen atom, i.e., RR'R''N. If the nitrogen carries four substituents, the compounds are Quaternary Ammonium Compounds. In secondary or tertiary amines the substituents may be the same or different. Two or more amino groups may be found on the same molecule, e.g., in diamines. The organic substituents in amines may be aliphatic, aromatic, or heterocyclic and may carry other functional groups.
Most amines which do not carry additional functional groupings exhibit unpleasant odors and are, therefore, not widely used in cosmetics. Amino Acids result if the additional substituent on the amine is a Carboxylic Acid grouping. Amides and Alkanolamides are formed from primary or secondary amines by reaction with a reactive species of a carboxylic acid. Aliphatic amines possessing a hydroxyl group, the Alkanolamines, are odorless bases and find use in the cosmetic industry to neutralize acids, e.g., in TEA-Lauryl Sulfate. The aromatic diamines and aminophenols are used extensively in oxidation-type hair dyes.
Alkanolamides, Alkanolamines, Amides, Amino Acids, PABA Derivatives, and Quaternary Ammonium Compounds are listed separately. |