Each one of the members of two classes of nitrogen-containing organic
compound, always contains a carbonyl group (-C = O).
1.
The first
class, amide kovalent is making by replacing the hydroxyl group (-OH) of the
amino acid group (-NR2, where R may represent a hydrogen atom or an organic
combining group such as methyl).
Amide formed from carboxylic acids, called carboxamides, is solid except or the simplest, formamide is in liquid
form. Amide
does not conduct electricity, has a high boiling point, and (when liquid) is a
good solvent. Peptides
and proteins in living systems is a long chain (polymer) with a peptide bond. Urea is an amide
with two amino groups. Commercial
amides, including some covalent used as a solvent, while the other is a sulfa
drug and nylon.
2.
The second
class, the amide ions (such as salt), prepared by treating a covalent amide,
amine or ammonia to the reactivity of metal (example sodium) and strong base. A
derivatives of carboxylic acids with RCONH2 as a general formula, where R is
hydrogen or alkyl or aryl radical. Amida
is divided into several sub-classes, depending on the number of substituents on
the nitrogen. Simple
or primary, that is an amide formed by replacing the carboxylic hydroxyl group
by an amino group NH2.
This naming compound name by dropping acid
"-ic" or "-OCI" origin of the name of the carboxylic acid
and replacing it with the suffix 'amide'.
In secondary and tertiary amides, one or both of
the hydrogen is replaced by other groups. The
existence of the group designated by the prefix N (for nitrogen).
Except for formamide, all the simple amides is
melted solid, stable, and weak acids. They
are strongly associated through hydrogen bonding, so soluble in the solvent
hydroxylic, such as water and alcohol.
Because of the ease of formation and a sharp
melting point, amides are often used for identification of organic acids and
amines identification. Commercial
preparation of amides involves thermal dehydration of the carboxylic acid
ammonium salt.
