Indian Forest Service Examina!i: • 2013 fcll{)>Jll DETACHABLE
CHEMISTRY
Paper II
I Time Allowed Three Hours I I Maximum Marks 200 I
QUESTION PAPER SPECIFIC INSTRUCTIONS
Please read each of the following instructions carefully before attempting questions.
There are EIGHT questions in all out of which, FIVE are to be attempted.
Question no. 1 5 are compulsory. Out of the remaining SIX questions, THREE are to be attempted
selecting at least ONE question from each of the two Sections A and B.
Attempts of questions shall be counted in chronological order. Unless struck off, attempt of a question shall
be counted even if attempted partly. Any page or portion ofthe page left blank in the answer book .must
be clearly struck off.
All questions carry equal marks. The number of marks carried by a question/part is indicated against it.
Answers must be written in ENGLISH only.
Unless otherwise mentioned, symbols and notations have their usual standard meanings.
Assume suitable data, if necessary and indicate the same clearly.
Neat sketches may be drawn, wherever required.
SECTION
1. Answer the following
l.(a)The base catalysed reaction of pyrrole with formaldehyde gives a compound, C20H14N4.
is it aromatic Explain with its importance in nature. 5
l.(b)Amines are more water-soluble than alcohol of similar molecular weights. Offer suitable
explanation for this fact. 5
Arrange the following carbocations in order of their increasing stability with reasoning: 5
<img src='./qimages/1289-1c.jpg'>
Compare the rates of SN1 and SN2 reactions of 1-chlorobicyclo [2·2·2] octane and
9-chloro decalin. 5
l.(e)Designate the reaction and products by heating 5

<img src='./qimages/1289-1e1.jpg'>

<img src='./qimages/1289-1e2.jpg'>
l.(f)Compare the reaction of H2C=CH2 and F2C=CF2 with KOEt in ethanol. 5
1.(g)The reactions of Grignard reagent and subsequent hydrolysis with compound A gives whereas
compound C gives in 100% yield. Explain with suitable reason. 5
<img src='./qimages/1289-1g.jpg'>

1.(h)Complete the following reaction with designation
Furfuryl alcohol Maleic anhydride

2.(a)(i)What is primary and secondary isotope effects
2.(a)(ii)Identify which of the reactions display primary isotope effect and which the secondary
effect 10
<img src='./qimages/1289-2a2.jpg'>

Discuss the molecular structure and physical properties of graphite. 10
Triphenylmethyl radical is not so stabilized by delocalization of the unpaired electron as expected.
Comment on this observation. 10
Why the following cyclic diol (squaric acid) is almost strong an acid as H2SO4?
<img src='./qimages/1289-2d1.jpg'>

The rotational energy barrier around the C-N bond of compound 2 is higher than compound I.
<img src='./qimages/1289-2d2.jpg'>

When (R)-2-bromopropanoate ion is treated with concentrated NaOH, (S)-2-hydroxypropanoate
ion is obtained. However, when the same reaction is carried out with a low concentration of
hydroxide ion in the presence of Ag2O, (R)-2-hydroxypropanoate ion is obtained. Account
for this observation. 10
3.(b)Give the stereochemistry of products formed when
trans-2,4-hexadiene reacts thermally
trans, cis, trans-2,4,6-octatriene reacts photochemically
Suggest a mechanism for the following reactions
src='./qimages/1289-3c1.jpg'>

src='./qimages/1289-3c2.jpg'>

Friedel-crafts acylation of azulene gives mainly one acylated product
<img src='./qimages/1289-3d.jpg'>

Which ring of azulene does undergo attack by CH3CO preferentially and why? Give the mechanism of the reaction. 10
4.(a)What is Steven's rearrangement Bring out the different mechanisms that have been
proposed for this rearrangement by giving the supporting evidences for each of them (including CIDNP studies). 20
4.(b)Outline the synthesis of the following as indicated showing the reagents used and mechanism. 5x2=10

4.(b)(i)C6H5CO CH2COOC2H5 from ethyl benzoate using Reformatsky reaction
4.(b)(ii)Cyclopentanone by Dickman condensation
4.(c)Using Skraup synthesis how would you prepare 5x2=10
4.(c)(i)4-Methyl quinoline
4.(c)(ii)3-Ethyl quinoline
SECTION

5. Attempt the following 8x5=40
5.(a)Natu1ral rubber and Gutta percha rubber, two polymers, have the same composition of monomers,
their properties are radically different. Account for this. 8
5.(b)Write the name and structure of the bases present in RNA and DNA. 8
5.(c)compound with molecular formula C6H10O shows the following IR and H NMR spectra.
Write the most probable structure of the compound.
<img src='./qimages/1289-5c.jpg'>
5.(d)Give the mechanism for the following conversion
src='./qimages/1289-5d1.jpg'>
<img src='./qimages/1289-5d2.jpg'>

5.(e)Discuss the synthesis of the following polymers showing their chemical reactions 4x2=8
5.(e)(i)Teflon
5.(e)(ii)Terylene
6. How would you convert the following Propose mechanism.
6.(a)<img src='./qimages/1289-6a.jpg'>
C6H5COCH2-CH2-COC6H5->C6H5COCH=CHCOC6H5
6.(c)<img src='./qimages/1289-6c.jpg'>
6.(d)<img src='./qimages/1289-6d.jpg'>

Predict the product(s) of the following:
src='./qimages/1289-7a1.jpg'>
src='./qimages/1289-7a2.jpg'>
src='./qimages/1289-7a3.jpg'>
src='./qimages/1289-7a4.jpg'>
src='./qimages/1289-7a5.jpg'>

7.(b)Write the products for the following reaction. Propose suitable mechanism for the formation of products 10
<img src='./qimages/1289-7b.jpg'>

7.(c)EPR spectrum of Bis-Salicylaldimine copper showed only eleven peaks instead of fifteen
peaks. Account for this. 10
8.(a)Propose a structure consistent with the following spectral data for a compound of molecular
formula C8H18O2
<img src='./qimages/1289-8a.jpg'>

8.(b)Explain why in the mass spectrum of bromobenzene, there will be two peaks at m/z 156 and 158
of approximately equal intensity. 10
8.(c)Which spectroscopic tool or tools NMR, IR) would you use to distinguish the two members
of each of the following pairs of compounds What features of the spectrum would be most
diagnostic of the structure
<img src='./qimages/1289-8c1.jpg'>
<img src='./qimages/1289-8c2.jpg'>
src='./qimages/1289-8c3.jpg'>
8.(d)A compound of m.f.C9H11N02 exhibits the following spectral characteristics. Assign a suitable
structure and account for the spectral data
<img src='./qimages/1289-8d.jpg'>