1. Aldehydes and Ketones Prepared by Dr.S.Ignatius Arockiam
Dept of chemistry

2. INTRODUCTION
Many of the names of aldehydes and ketones are derived from the names of the corresponding carboxylic acids.
The information about the nomenclature of carboxylic acids is very useful to give the nomenclature of aldehydes and ketones

3. Naming of Carboxylic acids R-COOH, R-CO2H, Common names
HCO2H Formic acid
CH3CO2H Acetic acid
CH3CH2CO2H Propionic acid
CH3CH2CH2CO2H Butyric acid
CH3CH2CH2CH2CO2H - Valeric acid

4.
C—C—C—C—C=O
δ γ β α used in common names

5. NAMING OF AROMATIC COMPOUNDS

6. ALDEHYDES AND KETONES
“carbonyl” functional group:
Aldehydes Ketones

7. NAMING OF ALDEHYDES FROM THEIR
COMMON NAMES
(i) To name the aldehydes remove –ic acid from the carboxylic acid
(ii) add the suffix aldehyde in the end of the compound.
CH3
CH3CH2CH2CH=O CH3CHCH=O
butyraldehyde isobutyraldehyde
(α-methylpropionaldehyde)

9. NOMENCLATURE OF ORGANIC COMPOUNDS
Select the longest one from the parent chain containing
the carbonyl group.
Remove the last letter “e” and then add “al” in the name of
the aldehyde.
HCHO Methanal
CH3CHO Ethanal
CH3CH2CH2CHO - butanal
CH3CH(CH3)CHO - 2-methylpropanal

10. COMMON NAMES FOR KETONES
- Dimethyl ketone

11. Ortho phenones:
Derived from common name of carboxylic acid, drop –ic acid, add –(o)phenone.

12. Ketones: IUPAC nomenclature
(i) Parent chain is the longest continuous carbon chain containing the carbonyl group.
(ii) drop –e, add –one. Prefix a locant for the position of the carbonyl using the principle of lower number.

13. Physical properties:
(i)Carbonyl compounds are polar in nature and there is no hydrogen bonding between the atoms
(ii)Melting and boiling points are relatively moderate for covalent substances
(iii) Compounds are water insoluble . Except the compounds having four carbons or less)

14. Spectroscopic analysis:
IR gives the spectroscopy gives the following strectching frequencies
Compound
Strectching frequency
(cm-1)
RCHO
1725
ArCHO
1700
R2CO
1710

15. Oxidation/Reduction: oxidation numbers
oxidation number of the compounds increases from alkane to carboxylic acid.
oxidation
CH CH3OH H2C=O HCO2H
alkane alcohol aldehyde carboxylic acid
reduction

16. Thank you