BSc Chemistry SEM V 2018 19 2018-19 Chemistry Organic Chemistry 19 Old Question Paper - Mumbai University | munotes

Questions asked in this paper

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1. Q3 Use of log tables/non-programmable calculators is allowed
2. Q1 Answer any three of the following:
   • (A) What is Michael addition? Explain its mechanism and give one application. 05
   • (B) Show that the reaction of conc. H2SO4 to naphthalene is a_ kinetically & 05 thermodynamically controlled reaction. Write its mechanism
   • (C) State and explain the Saytzeff rule with one example. Write the E; and Es mechanism. 05
   • (D) Write the reaction and mechanism for the following : 05 aldehyde reacts with two moles of dil. HCl
   • ii) <A carboxylic acid reacts with one mole of an alcohol in the presence of conc
   • (E) What is pinacol-pinacalone rearrangement? Write the mechanism and give one 05
   • (F) A ketoxime is treated with conc. Identify the reaction, write the reaction & the 05
3. Q2 Answer any three of the following :
   • (A) Explain the following terms : 05
4. Q1 alternating axis of symmetry
   • ii) Pitzer strain in cycloalkanes
   • (B) Discuss the conformation of 1,3-Dimethyl cyclohexane and explain the geometrical 05
   • (C) What is molecular chirality? Explain atropisomerism in substituted biphenyls with 05
   • (D) What are stereoselective reactions? Explain enantioselectivity and diastereoselectivity
   • (E) Discuss the stereochemical outcome of the following reactions: 05
   • Q.P. Code : 40357
   • (F) Justify the following statements : 05
5. Q1 reaction at an asymmetric carbon generally takes place with racemization
   • ii) boat form of cyclohexane has greater energy than the chair form
6. Q3 Answer any three of the following :
   • (A) a) Draw the Haworth’s formula of the following sugars 03 ii)
   • b) Explain the action of the following reagents on D-fructose 02
   • (B) Discuss the following reactions giving step-wise equations. 05
7. Q1 Complete methylation of D — fructopyranose
   • ii) formation in D — glucose
   • (C) a) What is Wohl’s degradation in sugars? Explain with a suitable example. 03
   • b) Give the commercial importance of carbohydrates in food industry. 02
   • (D) Explain the following terms with suitable examples. 05
8. Q1 and epimers
   • ii) Mutarotation
   • (E) a) Explain the action of HIO4 on D-glucose and D-fructose. 03
   • b) Give the conversion of D-fructose to D-glucose. 02
   • (F) Give the IUPAC names of the following: 05
   • Q.P. Code : 40357
9. Q4 Answer any three of the following :
   • (A) a) Explain Hofmann’s exhaustive methylation and elimination reaction with 03
   • b) Give Paal-knorr synthesis for the preparation of thiophene 02
   • (B) a) Explain Chichibabin reaction of pyridine. 03
   • b) Give resonance structure of pyrrole. 02
   • (C) a) How will you convert? 03
10. Q1 to thiophene 2- aldehyde
    • ii) Furan to 2-acetyl furan
    • b) Explain aromatic character of thiophene 02
    • (D) Explain linear & convergent synthesis. 05
    • (E) Give synthesis of the following : 05
    • (F) Explain the use of microwave in organic synthesis with any two examples. 05
11. Q5 (A) Choose the correct option and rewrite the statement : 4 marks
    • a) The carbocation is an example of a species (electron loving, proton loving electron donating, none of above)
    • b) An aromatic aldehyde reacts with a primary amine to form a
    • c) Claisen’s condensation proceeds through the formation of as areactive
    • (A) State whether the following statements are true or false 4
    • p) Nucleophiles are electron rich species
    • q) A acid-base reaction is a thermodynamically controlled reaction
    • r) The conversion of an amide to a primary amine in the presence of halogens and a strong base is called Hofmann’s rearrangement reaction
    • s) Base catalysed hydrolysis of ethers is called saponification
    • (B) State whether the following molecules are chiral or achiral: 04
    • Q.P. Code : 40357
    • (B) State whether the following are true or false: 04
    • p) All stereospecific reactions are also stereoselective
    • q) An chiral molecule contains at least one element of symmetry
    • r) Cyclopropane is less stable than cyclobutane
    • s) Cummulenes containing even number of double bonds exhibit geometrical isomerism
    • (C) Write the IUPAC Names of the following : 04
    • (C) Draw the structures of the following: 04
    • q) 4 [H] pyran
    • (D) Complete the following reactions. 03
    • (D) Match the columns : 03

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