M.pharm 1 st year NIKET BAJARE pharmaceutical chemistry

1. ADVANCED ORGANIC CHEMISTRY
Presented by : Niket D.Bajare [M.pharm First year]
Guided by :Dr S. Pekamwar
School of Pharmcy ,Nanded.

2. Mechanism and Synthetic Application of Naming
reaction
• DIECKMANN REACTION
• OZONOLYSIS REACTION

3. DIECKMANN REACTION
-It is named after the german chemist Walter
Dieckmann (1869-1925)
-certain diesters undergoes intramolecular condensation
in the presence of strong base to produce B-keto esters
this called as “Dieckmann condensation reaction”.
-its ring forming reaction.

4. General Reaction :-

5. Mechanism.......
-Deprotonation of an ester at the alpha-position
generates an enolate ion which then undergoes a 5-
exo-trig nucleophilic attack to give a cyclic enol.
-protonation with a Bronsted-Lowry acid reforms
the Beta-keto ester.

6. Mechanism.........

7. synthetic application..........
• It is used in the synthesis of various
cyclopentane &cyclohexane derivative.
• it is used in preparation of cyclic
indole.(active against cancer)

8. OZONOLYSIS

9. what is ozonolysis ?
• OZONOLYSIS is an organic reaction where the unsaturated
bonds of alkenes,alkynes or azo compound are cleaved with
ozone .
• alkenes and alkynes form organic compound in which the
multiple carbon-carbon bond has been replaced by a carbonyl
group.while azo compound form nitrosamines.
• the out come of reaction depends on the type of multiple bond
being oxidised and work up condition.

10. ozonolysis of alkenes.............
• alkenes can oxidised with ozone to form
alcohol,aldehyde,or ketone or carboxylic acid.
• e.g- tetramethyl alkene which is undergoes
ozonolysis in methanol at -78dc. to form the prop-
2-one and small amount of acids.

11. reaction

12. Mechanism ....
• The alkene and ozone form an intermediate molozonide
in a 1,3-dipolar cycloaddition.
• the molozonide reverts to its corresponding carbonyl
oxide and aldehyde or ketone in a retro-1,3-dipolar
cycloaddition.
• the oxide and aldehyde or ketone react again in a 1,3-
dipolar cycloaddition or produce a relatively stable
ozonide intermediate (a trioxolane )

14. Synthetic application....
• It is used for structure elucidation of unknown organic
compound containing carbon carbon double bond(c=c).
CH3 (CH2)7 CH CH (CH2)7 COOH CH3 (CH2)7 COOH
pelargonic acid
O31)
2) H2O2
Oleic acid
HOOC (CH2)7 COOH
Azelaric acid
+

15. References :-
• Organic chemistry Clayden, Greeves,Warren & Woihers .,
Oxford University.
• Wikipedia