Download Derivatives of Carboxylic Acids

Derivatives of
Carboxylic Acids
formulas
• Carboxylic acids and their derivatives can be
expressed as variation of a single formula in
which electronegative atom (O, N, or halogen) is
bonded to an acyl group (RC=O)
• Carboxylic acid -OH is attached to acyl group.
• Ester
-OR, alkoxy is attaches to acyl group
• Amide -NH2 is attached to acyl group
• Acid chloride -Cl is attached to acyl group
• Acid anhydride RCO
||
O
is bonded to the group of another (2 acids minus one molecule
of H2O
Uses
• Acids, esters and amides are abundant in nature
• Proteins are amides (amino acids connect by amide linkage)
• Ester linkages are found in fats, oils, and natural waxes. Their
pleasant odors are responsible for the taste and fragrance of
fruits and flowers.
Nomenclature of Acid
derivatives
• Esters: Change –oic acid to –ate and precede the name with
alkyl group. (alcohol + acid)
• Amides: Change –oic acid to amide
Preparation of Esters and
Amides
• Preparation of Esters : condensation reaction between alcohol
and acid
O
||
ROH + R’COH  ROCR’ + H2O
• Amides: condensation reaction between an acid
and NH3 or an amine.
O
O
||
||
RCOH + HNR’  RCNR’ + H2O
Aspirin and other Analgesics
• Pain relievers are among the most important
medicinal application of carboxylic acid
derivatives. Aspirin is acetyl salicylic acid,
salicylate ester of acetic acid.
• Salicylic acid is a bifunctional molecule (acid and
phenol) which is itself a disinfectant.
• Aspirin comes from the willow bark which was
used in the Middle Ages by Jesuit missionaries.
Amines
• Amines are derivatives of ammonia, NH3, in which one or
more hydrogens have been replaced by organic groups.
• If one H is replaced it is primary
• If two H are replaced, it is secondary
• If three H are replaced, it is tertiary.
• Aromatic groups make it an arylamine.
Nomenclature
• Simple amines can be named acceptably by
common nomenclature as alkyl amine in which
amine is added to the name of the organic
group.
• If IUPAC nomenclature, the suffix –amine is
added to the name of the longest continuous
carbon chains possessing the functional group.
• Change the –e to amine.
• Phenylalkyamines have benzene ring, alkyl group
and amine