SYNTHESIS AND SPECTRAL STUDIES OF ORGANIC

advertisement
CLASS: B.SC. CHEMISTRY
J191A7
ST. JOSEPH’S COLLEGE (AUTONOMOUS), TIRUCHIRAPPALLI - 620 002
SEMESTER EXAMINATIONS – APRIL 2007
TIME: 3 Hrs.
MAX. MARKS: 100
SEM
SET
PAPER CODE
SUBJECT
VI
2004
04UCH631
SYNTHESIS AND SPECTRAL STUDIES OF ORGANIC
COMPOUNDS
SECTION – A
Answer all the questions:
10 x 3 = 30
1. Give the differences between Resonance and Tautomerism.
2. Complete the following reaction:
Zn
CH3CHO + BrCH2COOEt
3. With suitable example explain nitro – acinitro tautomerism.
4. Among the following amines which one is more basic? Give reason:
Aniline, Methylamine
5. Complete the following reaction:
CHCl3
Pyrrole
KOH
6. What is peptide bond? Give an example.
() 2.5 x 10-4cm.
7. Calculate the wave number corresponding to wavelength
8. Which of the following compounds has higher max. Give reason:
a) Acetone
b) acetaldehyde
c) propenal
9. Give the NMR peak pattern obtained from EAA.
10.Complete the following reaction:
d) ethanol
Ph
Ph
Me – C – C – Me
H
OH OH
SECTION – B
Answer all the questions:
11. a.
5 x 14 = 70
How will you prepare the following compounds from EAA.
i) Ethyl methyl ketone
ii) 3 – phenyl propanoic acid
(7)
b. Effect the following conversions:
i) Glucose
Fructose
ii) Arabinose
Glucose
(7)
(OR)
b. With illustration define:
i) epimers and (ii) anomers.
(4)
d. i) Give the structure of Sucrose and Maltose.
(4)
ii) Effect the conversion.
DEM
12. a.
(6)
COOH
With illustration explain:
i) Sandmeyer reaction and (ii) Hofman elimination.
(6)
b. Give the preparation and synthetic applications of diazomethane.
(8)
(OR)
c. Discuss the reduction products of nitrobenzene at different conditions.
(8)
d. Predict the product and suggest mechanism
Br2 / NaOH
PhCONH2
(6)
13. a. With orbital picture explain the aromatic character of pyrrole. (5)
b. Define the following terms with suitable example.
i) Antibiotics
ii) Antiseptics
iii) Vitamins
(9)
(OR)
c. Discuss the secondary structure of protein.
(5)
d. Complete the following reactions:
(9)
i) Furan + maleic anhydride
Al2O3
ii) 2 Acetylene + H2S

liq.NH3, NaNH2
iii) Pyridine
14. a. Explain the principle involved in Mass spectrometry.
(6)
b. Define the following spectroscopic terms:
i) Chromophore
ii) Finger print region
iii) Base peak
iv) Parent peak
(8)
(OR)
c. Suitable example explain McLafferty rearrangement.
(6)
d. Calculate the max for the following compounds:
O
(8)
i)
15. a.
ii)
Define the following terms:
i) Chemical shift
(6)
ii) Spin – spin splitting.
b. The compound of MFC10H12O2 has the following NMR data
 = 7.2 (S, 5H) ;  =
3.3 (S, 2H) ;  = 2.1 (t, 2H)  = 1.6 (d, 3H). It shows characteristic IR frequency at
1740cm-1. Assign the possible structure of the compound.
(8)
(OR)
c. Explain the mechanism of Benzilic acid rearrangement. (6)
c. Write note on:
i) ESR spectroscopy
(8)
ii) 13CNMR
***************
Download