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 ***************