Carboxylic Acids

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Organic Chemistry
Chapter 10
Part I
Carboxylic Acids and Their
Derivatives (Ester)
Nanoplasmonic Research Group
Carboxylic Acids (General)
carboxyl group
three ways to represent a carboxylic acid
acid derivatives
• Organic Acids characterized the presence of
a carboxylic group
• Bronsted-Lowry acids: Proton donors
• Salts or Anions: Carboxylates
Nomenclature
• In IUPAC nomenclature: carboxylic acids have
an -oic acid suffix
• In common nomenclature, the suffix is usually
-ic acid
Physical Properties of Carboxylic Acids
• Polar and form hydrogen bonds with each
other
• At high T, in vapor phase, carboxylic acids
usually exist as dimeric pairs
• Water solubility: Chain-length dependent
Acidity of Carboxylic Acids
• The acidity can be explained by either the
stability of the acids or the stability of the
conjugate base using inductive effect or
resonance effect
• The stability of the acids: Inductive effect
• The stability of the conjugate base: Both
Synthesis of Carboxylic Acids
• Oxidation of Primary Alcohols and
Aldehydes
• Hydrolysis of Nitriles, Esters, or Amides with
The Addition of Acid or Base
Roles of Acid or Base !!!!!! (page 298, 10.15)
• Reaction of Grignard Reagents with Carbon
Dioxide
Carboxylic Acids Derivatives
(Ester)
• The R part of the -OR groups is named first ,
followed by the name of the acid, with the
-ic ending changed to -ate
• Ocurrence: the flavor and fragrance of many
fruits and flowers
• Hydrogen bond acceptor: Volatile than
carboxylic acids
• Cyclic ester: Lactone
How to Prepare Ester ??
- Fischer Esterification -
• Refluxing a carboxylic acid in an alcohol,
which acts as both solvent and reactant
• Since the reaction is an equilibrium, how to
push the equilibrium to the right ????
le Chatelier’s principle !!!
How to Push the equilibrium to the
right ?
- Fischer Esterification -
• Using the alcohol as a solvent (in large
excess)
• Using Sulfuric Acid: It acts as an acid catalyst
and as a dehydrating agent
• Distillation (boiling point)
What happens to Fischer
Esterification ?
•
•
•
•
Nucleophilic Acyl Substitution !!!
Please take a look at eq. 10.19 on page 301
Protecting group
Tetrahedral intermediate
Reactions of Esters
• Saponification, Reduction, Ammonolysis, and
Reaction with Grignard Reagent
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