N A L A N D A O P E N U N I V E R S I T Y
M.Sc. Chemistry, Part-I
PAPER-III
(Organic Chemistry)
Annual Examination, 2017
Time 3 Hours. Full Marks 80
Answer any FIVE Questions.
All questions carry equal marks.
1. Explain arommaticity and give details of Huckle molecular orbital theory.
2. Explain the conformations of Dimethyle Cyclohexanes.
3. Explain why aniline is more reactive than acetanilide in electrophilic substitution.
Chlorobeuzene is far less reactive than aniline in electrophilic substitution although
chlorine and nitrogen have almost the same electronegalivity.
4. What are Carbens How are they generated Give the important reactions of Carbens.
5. Explain the following
-NH2 group is ortho and para directing group.
-NO2 group is meta-directing group.
Halogens are ortho and para directing group.
6. What do you mean by aromatic nucleophilic substitution Explain aromatic substitution
unimolecular Nucleophilic reaction.
7. Explain conformation of cyclohaxane and also discuss the effect of conformation on chemical
reactivity.
8. Write notes on any Two of the following
Aldol addition reaction.
Mannich reaction.
Benzoin Condensation.
Perkin Reaction.
9. Discuss with suitable examples
Plane of symmetry.
Reflection symmetry.
10. Explain the mechanism of Elimiation Bismolecular reaction with suitable examples.