Guru Nanak Dev University 2007-2nd Sem B.Sc Chemistry ORGANIC OF FUNCTIONAL GROUPS-II (CHEM-202) (-2k7) - Question Paper
2057
B.Sc.(H.S.) Chemistry second Semester
CHEMISTRY
Paper : Chem-202
(Organic Chemistry of Functional Groups - II)
Time Allowed : 3 Hours
Maximum Marks : 75
part - A
(10 x 1½ = 15)
Note :- Attempt ALL ques. of this part. every ques. carries 1½ Marks.
1. Sketch the synthesis of DDT.
2. refer to attachment.
3. How will you synthesize isopropyl alcohol from :
(a) Acetone
(b) Propene ?
4. How will you convert phenol into :
(a) Salicyllic acid
(b) o-Hydroxyacetophenone ?
5. Electron releasing groups reduce the acidity of phenols while electron with drawing groups enhance the acidity of phenols, discuss.
6. How will you discuss the acidity of a-hydrogen in case of carbonyl compounds ?
7. Write down 2 methods for the conversion of acid chlorides to aldehydes.
8. How will you synthesize benzoic acid from bromobenzene ?
9. Why ethyl p-nitrobenzoate is saponified at much faster rate as compared to ethyl benzoate ?
10. refer to attachment
part - B
(8 x 4½ = 36)
Note :- Attempt any 8 ques.. every ques. carries 4½ marks.
11. refer to attachment
12. explain the effect of polarity of solvent and nature of nucleophile on the reactivity of Sn1 and Sn2 reaction.
13. Reaction of 3,3-dimethyl-2-butanol with HCl outcomes in the formation of 2-chloro-2,3-dimethylbutane rather than 2-chloro-3,3-dimethylbutane. Account for this outcome and also write the mechanism.
14. Write the mechanism of Fries rearrangement. How will you establish that the reaction involves 2 step mechanism ?
15. How will you prepare cis-1,2-cyclohexane diol and trans-cyclohexane diol from cyclohexane ?
16. explain the mechanism of Canizzaro reaction. Which kind of aldehydes provide this kind of reaction ?
17. refer to attachment
18. Write the mechanism of base catalyzed halogenation of enolisable ketones. What ia the limitation of the reaction ?
19. Write 1 method for conversion of carboxylic acid to acid chloride, ester and amide.
20. refer to attachment
21. How will you synthesize malonic acid from chloroacetic acid ? define the action of heat on succinic acid and adipic acid.
22. Why amides are less reactive than acid chloride towards acyl nucleophillic substitution reactios ? How will you convert acid anhydride into ester and amide ?
part - C
(2 x 12 = 24)
Note :- Attempt any 2 ques.. every ques. carries 12 Marks.
(Please refer to the attachment for the ques. in Section-C) 7102
A
B.Sc. (H.S.) Chemistry 2nd Semester "v CHEMISTRY Paper : Chem-202 (Organic Chemistry of Functional Groups-II)
Time allowedThree Hours] [Maximum Marks75 SECTIONA Note :Attempt ALL the questions of this section. Each question carries 1-5 marks.
/rr Sketch the synthesis of DDT.
Arrange the following alkyl halide in order of increasing reactivity towards SN1 type of reaction :
 2nd Sem (May, 2k7)_files/3714-10831-ORGANIC CHEMISTRY OF FUNCTIONAL GROUPS - II (CHEM - 202) 2nd Sem (May, 2k7)-1.png)
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(i) |
 2nd Sem (May, 2k7)_files/3714-10831-ORGANIC CHEMISTRY OF FUNCTIONAL GROUPS - II (CHEM - 202) 2nd Sem (May, 2k7)-2.png) |
 2nd Sem (May, 2k7)_files/3714-10831-ORGANIC CHEMISTRY OF FUNCTIONAL GROUPS - II (CHEM - 202) 2nd Sem (May, 2k7)-3.png)
 2nd Sem (May, 2k7)_files/3714-10831-ORGANIC CHEMISTRY OF FUNCTIONAL GROUPS - II (CHEM - 202) 2nd Sem (May, 2k7)-4.png)
&How will you synthesize isopropyl alcohol from :
(a) Acetone
(b) Propene ?
4. How will you convert phenol into :
aSalicylic acid
(b) o-Hydroxyacetophenone ?
v
, /Electron releasing groups decrease the acidity of phenols while electron with drawing groups enhance the acidity of phenols, explain.
i"T How will you explain the acidity of a-hydrogen in case of carbonyl compounds ?
Write down two methods for the conversion of acid chlorides into aldehydes.
j""'low will you synthesize benzoic acid from bromobenzene ?
fi.-'Why ethyl p-nitrobenzoate is saponified at much faster rate as compared to ethyl benzoate ?
40TIdentify the compounds A, B and C in the following sequence of reaction :
.COOH L socl
- >A-2-2->B
II. NH3
H.O/H C<2-
SECTIONB Note :Attempt any EIGHT questions. Each question carries. 4-5 marks.
4i'THow will you explain the fact that allyl chloride undergoes substitution through SN1 mechanism whereas propyl chloride reacts through SN2 mechanism ?
7102 2 (Contd.)
'J' -V; ,
1 Ji. ~
12. Discuss the effect of polarity of solvent and nature of nucleophile on the reactivity of SN1 and S 2 reaction.
% jflleaction of 3, 3-dimethyl-2-butanol with HC1 results in the formation of 2-chloro-2, 3-dimethyl butane rather than 2-chloro-3, 3-dimethyl butane. Account for this result and also write the mechanism.
 2nd Sem (May, 2k7)_files/3714-10831-ORGANIC CHEMISTRY OF FUNCTIONAL GROUPS - II (CHEM - 202) 2nd Sem (May, 2k7)-5.png)
Write the mechanism of Fries rearrangement. How will you establish that the reaction involves two-step -ncchanism ?
 2nd Sem (May, 2k7)_files/3714-10831-ORGANIC CHEMISTRY OF FUNCTIONAL GROUPS - II (CHEM - 202) 2nd Sem (May, 2k7)-6.png)
How will you prepare cis-1, 2-cyclohexane diol and trans-cyclohexane diol from cyclohexane ?
16. .Discuss the mechanism of Cannizzaro reaction. Which
type of aldehydes give this type of reaction ?
17. Complete the following reactions :
 2nd Sem (May, 2k7)_files/3714-10831-ORGANIC CHEMISTRY OF FUNCTIONAL GROUPS - II (CHEM - 202) 2nd Sem (May, 2k7)-7.png)
 2nd Sem (May, 2k7)_files/3714-10831-ORGANIC CHEMISTRY OF FUNCTIONAL GROUPS - II (CHEM - 202) 2nd Sem (May, 2k7)-8.png)
O
 2nd Sem (May, 2k7)_files/3714-10831-ORGANIC CHEMISTRY OF FUNCTIONAL GROUPS - II (CHEM - 202) 2nd Sem (May, 2k7)-9.png) |
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t- |
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I. (CH,C0),0/A1C1, |
 2nd Sem (May, 2k7)_files/3714-10831-ORGANIC CHEMISTRY OF FUNCTIONAL GROUPS - II (CHEM - 202) 2nd Sem (May, 2k7)-10.png) |
(iii)
*18-.-"Write the mechanism of base catalyzed halogenation of enolisable ketones. What is the limitation of this reaction ?
M<"write one method for conversion of carboxylic acid to acid chloride, ester and amide.
Complete the following reactions :
CHCH3 HCHO/(CHANH
 2nd Sem (May, 2k7)_files/3714-10831-ORGANIC CHEMISTRY OF FUNCTIONAL GROUPS - II (CHEM - 202) 2nd Sem (May, 2k7)-11.png)
-12->
CH0 OH
(Qf + CHjCHjCHO
s
O
(J1}
C,H,COOOH
->
21. How will you synthesize malonic acid from chloroacetic acid ? Describe the action of heat on succinic acid .and adipic acid.
*22. Why amides are less reactive than acid chloride towards acyl nucleophilic substitution reactions ? How will you convert acid anhydride into ester and amide ? '
7102 I 4 (Contd.)
(fv >
J n
-V
 2nd Sem (May, 2k7)_files/3714-10831-ORGANIC CHEMISTRY OF FUNCTIONAL GROUPS - II (CHEM - 202) 2nd Sem (May, 2k7)-12.png) |
/ SECTIONC |
Note : Attempt any TWO questions. Each question carries 12 marks.
23. (a) Explain the addition-elimination mechanism for nucleophilic substitution in aryl halides. Which type of aryl halides gives substitution through this mechanism ?
(b) Explain why aryl halides are inert towards nucleophilic substitution by SN1 and SN2 mechanism. 8,4
\24c''"lp"What is cumene hydroperoxide process for ,j synthesis of phenol ? Write its mechanism.
Write the mechanism of oxidative cleavage of 1, 2-glycol with HI04> 7,5
25>a)/tVrite the mechanism of Reimer- Tiemann reaction.
How will you prove the intermediacy dichlorocarbene in this reaction ?
(by The bromination of phenol takes place without the presence of catalyst while the bromination of benzene requires catalyst. Explain, why ? 8,4 26. (a) Discuss the orientation of ring opening reaction of unsymmetrical epoxides under acidic and basic conditions.
(b) Discuss the Aac2 mechanism of ester hydrolysis. How will you establish that the reaction involves an intermediate not a transition state ? 5,7 7102 5 100
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Attachment: |
| Earning: Approval pending. |
