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-II
PAPER-XV
(Organic Synthesis)
Annual Examination, 2017
Time 3 Hours. Full Marks 80
Answer any FIVE Questions.
All questions carry equal marks.
1. Explain synthons and synthetic equivalent. Discuss Retrosyntheitc analysis of C-C
disconnection and C-N disconnection.
2. Write mechanism of each of following rearrangements
Favourskii Rearrangement. Claisen Rearrangement.
Wegner-Meerwein Rearrangement. Arndt EisAert Synthesis.
3. Explain the synthetic use of H2O2 and O5O4 in the oxidation of alkene to glycol.
4. How thio alcohol may be prepared from alcohol How does it react with Acetone,
Mercuric oxide, Lead acetate, and Acetyl Chloride.
5. Write notes on any Three of the following
Sulpha drug Desulphururisation
Mustard gas T.N.T.
6. Give your reasons, predict the structure of principal product from pinacol rearrangement of
flowing glycol
2-Methyl-2, 3-Pentanediol. 2-Methyl-3-Phenyl-2, 3-butanediol.
4-Diphenyl-3, 4-hexanediol. 2-Diphenyl-2-Methyl-1, 2-prodpanediol.
7. Explain the synthetic use of NaBH4. Compare reductions wing NaBH4 and LiAlH4.
8. Explain the reduction reaction of the following compounds with examples
Reduction of Aldehyde. Reduction of Ketones.
Reduction of nitro Compounds.
9. What is silance How they are named Name the following compounds
CH 3HSi 2 CH 3 2SiCl 2
C 2H 5 2 SiHoocCH 3 2H 5Si OH 3
H 3Si SiH 2 3SiH 3
10. Write notes on the following
Eibs reaction Oppenauer oxidation
Etard reaction Barton reaction