Time Allowed: 3 hours Maximum Marks: 300
Candi dates should attempt Question Nos. 1 and 5 which are compulsory, and any three 0 f the remaining questions selecting at least one question from each Section. Assume suitable data if considered necessary and indicate the same clearly.
'AMfrER mit

SECTION A
1. Answer any TREE of the following:


HN02 is treated with separately in acidic medium. "What are the products?
l6J
If undergo es nu c1 eo phili c sub stituti 0 n re acti on, wh at are the fav 0 ure d
positions? Explain mechanistically. x 10=20)

How the aromaticity of a molecule can be judged from 1H NMR spectrum? "Which thermodynamicdatais concrete evidence?

Pyrrole with acid (strong) makes a red coloured comp ound. "What is its chemi cal nature?



Potential Energy changes during rotation about bond of n-butane. Present the vanation semi-quantitatively wi. th ro tati on 0 f thebond.


"What are the products formed when (CH3)2C C(CH3)2 reacts with CHCh and
NaOH? 2x 10= 20)




....:8 and ......D
2. Ozonolysis of Ii c:...o ("Where B &D are stronger electron donor than A and pro duces four ozonides. Explain mechanistically.

Butadiene on reaction with Br-F (mole ratio 1 pro duces two products. Explain.

k......,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,..... .....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....,.....

C6H5-Cl on reaction with NaOH in an autoclave produces phenol diphenyl ether and p-phenyl phenol. Explain the mechanism of formation.




"W'hy p-nitro benzaldehyde does not follow benzoin condensation? Explain.




C6H5CHO is refluxed in the presence of NaOH and excess HCHO Write the meg or aromatic product.



3. Identify the intermediates and products:
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II
4Hs -ClIO CH3C-Oi] --base A
;to
Acid
B .
CH2(G¥t)l
Base
1.. J-.butadie:n.e (excess) p-benzoquincne
heat heatec;1 ZIt+­
A B C
atSWC wlIhSe add

K

00.11 (aj RefIt£( wUh D

" B mild ht!.el C Filtered..filtrate ti treated. wttb.NH"
2.0
10
QBr_
A B
CO,II.


Identify the products m the followmg reactions
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U
R
CHO

OJ




u,N uP,

(ij Z" He!

UNO,.
00;100

SEcnON B
Answer any THREE of the followmg
Usmg Woodward-Fe!Ser rule predict the for the followmg m the1f electrolllc spectra


What are Nomsh type I and II photo-cleavages?
(2xIO=20)
The NMR spectrum of molecule BrCI has two doublets with J 16 Hz
Write its structure Wlth reason
For syntheSis of polyester, glycol IS treated with dimethylterphthalate but not phthalic
aad, Explam
(2xIO=20)
Explam the appearance of rrJz 44 peak m the mass spectrum of CH3CH,CH,CHO
The dehydration 0 f 2-dimethyl cyclohexanol (CiS or trans) giVes three alkenes, How
can you distingUlsh them on the baSiS ofthetr IR spectra?
The geometric !Somers of stilbene show at 278 and 294 run (2xIO=20) AsSign each value to
appropnate Isomer and sketch them
Write reagent(s) for the followmg converSiOn

...........



1R
L-.
0110H
x 10= 20)
6. Identify A-D in the following



x 4 20)
"W'hat are products fonned by photo dimerizati on of cyc1opent-2-en-l-one?

How adipic acid can be produced from phenol (only tw"o step

3-dimethyl-2 -chloro butane on E2 dehydrohal ogenation gives how many products? Can
they be distinguished by IR spectroscopy? Justify your answer.

7. Explain the mechanism 0f following transformation:


D

4 2 cyc1oaddition is thennally allowed. Explain through HUMO and LUMO.

"W'hat i s the hybridization of DNA?

Mechanical strength 0f Nylon is better than polyester. Explain.

"W'hy does B::lH6 follow anti-Markovnikovs addition to..


8. How and H3C-C=CH are di stingui shed by JR sp ectro scopy and proton NMR
sp ectro scop y Give meth0d for chemi cal sep arati on 0f th e tw"o co mp 0un ds.

How is azelaic aci d obtained from oleic acid?
Azelaic acid HOOC(CH::l)lCOOH
Oleic acid CH3(CH::l)rCHCH(CH::l)lCOOH.

A cyc10nitrile can be polymerized by base catalyzed reacti on but not by acid catalyzed
re acti 0n. Expl ain.
In the mass spectrum of CH3CH::lC-OCH3 the peaks atm/z 57,59,88 appear. Explain.
II
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