Post on 28-Dec-2015
Aldehydes & Ketones
Carbonyl Compounds C = O They are organic compounds containing a carbonyl
group they are divided into:
Ketones
CnH2n+2CO, R – CO – R R= R we have simple or symmetrical ketones
R ≠ R we have unsymmetrical ketones
Aldehydes & Ketones
Preparation:
1. Oxidation of primary alc. gives aldehydes while secondary alcohols give ketones.
Aldehydes & Ketones
Preparation:
2. Dry distillation of salts of acids: Calcium salts are generally used in this reaction.
Aldehydes & Ketones
Preparation:
5. When acetylene is passed into hot dilute sulphuric acid in presence of mercuric sulphate.
Aldehydes & Ketones
Chemical Reaction: Most of the reactions of aldehydes and ketones are
the reactions of the carbonyl group C = O.
The activity of this group arises from the displacement of electrons towards the more electronegative oxygen atom which imparts a positive charge on the carbon atom as follows:
Aldehydes & Ketones
Chemical Reaction:
It was found that the reactivity of the carbonyl group depends on the nature of the alkyl groups attached to it.
the smaller the group, the more reactive is the carbonyl group. Thus, the order of reactivity is:
Aldehydes & Ketones
Chemical Reaction:
A- Addition Reactions:
3. Action of NH3: Formaldehyde is an exception, it gives a complex
compounds known as amino form or Urotropine or hexa methylene tetra amine.
Aldehydes & Ketones
Chemical Reaction:
A- Addition Reactions:
3. Action of NH3: The structure of hexamthylene
tetra amine appears to be a complicated ring compound.
It is solid used in medicine for treatment of Gout and Rheumatism.
Aldehydes & Ketones
Chemical Reaction:B- Condensation Reaction:
Is the reaction of two or more molecules identical or different together with the elimination of water molecule.
1. With hydroxyl amine:
Carboxylic Acids (Fatty acids)
The functional group in this series is the carboxylic group – COOH which result from the combination of a carbonyl and hydroxyl group.
The carboxylic group is univalent so it is a terminal group.
Carboxylic Acids (Fatty acids)
Acids are classified into mono, di-, and poly- carboxylic acids, according to whether they contain one, two, or more carboxylic groups in the molecule.
Carboxylic Acids (Fatty acids)
1. Mono carboxylic acids: These contain one carboxylic group they
are mono basic, there general formula
CnH2n+1.COOH
Carboxylic Acids (Fatty acids)
It is produced in the commercial scale by heating carbon monoxide & sodium hydroxide at moderate temp. & pressure
Carboxylic Acids (Fatty acids)
Chemical reactions:
1. With strong electropositive metals, with the libration of hydrogen and formation of salts.
Carboxylic Acids (Fatty acids)
Chemical reactions:
- In case of chlorine or bromine in presence of small amount of red phosphorous, it gives alphahalogenated acids.