SRI CHAITANYA NARAYANA IIT ACADEMY

ORGANIC CHEMISTRY

IIT JEE 2019

HYDROCARBON
Teamma es

ALKYL HALIDE

ARYL HALIDE

PREPARED BY: ASHISH SIR & NEHA MADAM

SYNOPSIS

ALKYL HALIDE

EXERCISE-A (SN2)

One ofaMore Answer Correct

Cl

1. 
NaI
 [M], is

Cl
Me2 CO
SN 
2

Br
Imus Br

(A) (B)

Cl to
Br

Cl Cl

(C) (D)

Iad
Br to
Br

Br
Hat aCH  N  , is
2

2. x
3
 OH  
SN
at
H

HO H H CH

(A) Hk e (B) HOa pH 3

ayCH 3 xx

HO
(C) Ha pCH 3
(D) None

KAH

3. Me H

KSH
  O  , is

Et D  SN 2 

SH H

Me H Me H

(A) Et (B)
D Et D

H SH

H SH

HS Me H Me
(C) (D)

Et D Et D

H H

Cl
4.    P  is :
 Excess 
NaOH

Cl

O Cl

(A)
OH
(B)
OH

OH OH

(C) (D)
OH Cl

OTs


5. 
AcO Na
[Q] is –
tert-Bu

OAc

OAc
(A) tert-Bu (B)

tert-Bu

(C) tert-Bu (D) tert-Bu OAc

6. The structure of the major product formed in the following reaction :-

Cl

NaCN
DMF
 [R] is –

CN
Cl

(A) (B) NC

CN

Cl CN
(C) (D)

CN I

7. Which of the following compound will not undergo Nucleophilic substitution reaction :-

Cl Cl
Cl

(A) (B) (C) (D)

Cl

8. Conaider
i the given reaction :

CH3

H C OTs 
NaCN
 CH3 – CH2 – CH – CN

C2H5 CH3

Which of the following statements(s) is (are) correct for above reaction :-

(A) Product formation takes place due to breaking of o–Ts

(B) The reaction is SN2.

(C) Stereospecific reaction

(D) Configuration of product is (R).

9. Rate of SN2 will be negligible in –

Br
Br Br Br

(A) (B) (C) (D)

10. The major product of the following reaction is :-

Me Br

F
PhSNa

dimethyl formamide [S] is

NO2

Me SPh Me SPh Me Br Me SPh

F F SPh SPh

(A) (B) (C) (D)

NO2 NO2 NO2 NO2

11. The major product of the following reaction is :-

NH
(i) KOH
[T] is –

(ii) KOH Br CH2Cl

O MM

O O

C C

(A) N CH2 Br (B) N CH2 Cl

C C

O O

O O

C C
(C) N (D) N

C C

O CH2 Br O CH2Cl

12. The reaction

+SOCl2
N
+SO2 +

HO H
H Cl N
Cl

Proceeds by the mechanism :-

(A) SN1 (B) SN2 (C) SNi (D) NGP

13. The major product of the reaction shown :-

CH3

H Br NaCN

[U] is (are) :
H3C H DMSO, 25°C

CH2CH3

CN H
H

H3C CN CH3 H

(A) (B)
CH2CH3 CH3 CH3

H CH2CH3

CH3 CH2CH3

CH3 H
H CN

(C) (D) CH3 H

H CN CH3

CH2CH3

H H PhSNa

14. DMF
[V] is
Ph Cl

Cl SPh
(A) (B)

PhS

H H

(C) (D) Ph – S – Ph
Ph SPh

15. What will be the final product?

Cl

NaI
[W]
Me2CO

O ONa ONa O

Cl Cl Cl I

(A) (B) I (C) (D)

  1 NaH 1eq

16. CH3 – CH2 – OH 

 2  Ph – CH2 –Br  [X] is (are) :

(A) CH3 – CH2 – Br (B) CH3 = CH2

O
Et

(C) (D) Ph – CH2 – CH2 – CH3

17. Choose the product of the following reaction :-

CH3 O

IIEme
(1) Cl – S – – CH3

n O [Y] is (are) :

(2) NaN 3/DMSO

CH3 CH3 CH3 CH3

N3

(A) (B) (C) (D)

N3

18. 
NBS
 [M] 
KSH
 [N]
CH3

Identify the product [N] is(are) :

SH I Br Br

(A) (B) (C) (D)

Br SH SH SH

19. What product(s) would you expect to obtain from the following :-

H

NaOCH3
 [Z] is (are) :
CH 3OH

H3C

CH3 CH3 OH
OCH3 OH OCH3 H

(A) H (B) H (C) (D)

OCH3 H OCH3
CH3 OCH3 CH3 OH

20. Find the reltionship between teh major final product [M] & [N] of given reaction sequences :

H2

Pd – BaSO4
[M]
NaNH2 CH 3 – I

CH3 – C CH [W] [Y]

Na

Liq. NH3
[N]

(A) Identical (B) Functional isomers

(C) Diastereomers (D) Position isomers

21. Choose the major product of following reaction sequences :-

CH3

Cl – S – – CH3

(1) BH3, THF O NaI

[Major]
(2) H2O2, OH Acetone

CH3 CH3 CH3 CH3

I I I

(A) (B) (C) (D)

22. Predict the major product of given reaction sequence :

SH

(i) 2NaNH 2
[X] is(are) :
(ii) Et-Br (1 mole)

(iii) H
+

OH

S–CH2CH3 SH S–CH2CH3 SH

Et

(A) (B) (C) (D)

O–CH2CH3 OEt OH OH

23. Most reactive towards SN2 reaction is :-

O O

Cl
(A) Ph (B) Ph Cl

(C) CH3Cl (D) CH3O – CH2Cl

OH

24. 
NaH
 [P] 
CH3  I
 [Q], C5H12O

OH


TsCl
 [R] 
CH 3ONa
 [S], C5H12O

Correct relationship between [Q] & [S] is :

(A) Diastereomer (B) Enantiomer

(C) Structural isomer (D) Identical

25. In which of the given reaction (s), configuration about chiral (C) is (are) retained :-

Me Me

(A) H OH 
Na
 
CH 3Br
 (B) H OH 
TsCl
 
CH3ONa


Et Et

Me

(C) H OH 
Pcl5
 
CH 3 ONa
 (D) None

Et

26. What is the major product of the following reaction :

Br

HO 
NaH


(A) Br (B) O (C) (D) HO

NaI 1 mole 

27. H F   Product is :-

Br H Me 2 CO

(A) I F (B) H F (C) H H (D) H I

H H I H Br I Br H

28. What are the reactant [x] and product [y] in the following reaction sequences :-

O
H3C – – S – Cl

H3C O–S– – CH3

O NaN3

Reactant [x] O Product [Y]

Py ethanol H2O

H H

H3C OH CH3 N3 H3C OH H3C H

(A) (B)
N3

H H H H H H H

[x] [y]

H3C H H3C H H3C H H 3C N3

(C) (D)
H OH H N3 H OH H H

29. The best sequence of reaction of prepare 2-heptanone is :

  M     N  
 
n  C4 H9 Br
(A) Propyne  
NaNH2 Hg ,H

H2 O

  O    P  
 

(B) Ethyne 

NaNH 2 n  C5 H11Br Hg ,H
H2O


  Q     R  
 
CH  Br
(C) 1-Hexyne   
2 NaNH3 Hg ,H

H2O

 S    T  

 
CH  Br
(D) 1-Pentyne   
2 NaNH
3 Hg ,H
H2O

30. Which of the following is (are) SN2 reaction (s) ?

H Cl aq. OH OH H +Cl

(A) Cl 
 NaOH
H2O OH + NaCl (B)

Cl OH

Cl OH
CH3 H 2O CH3 + CH3 OH

(C) 

aq.NaOH
+ NaCl (D)

31. In which of the reaction(s) final product is ketons :-

i   M     N    O
CH 3  I
(A) CH 3  C  CH 
NaNH3 HgSO 4

H 2SO 4 ,H 2 O

(B) CH  CH 
NaNH2
  P  
CH3CH2 I
  Q 2 2
  Q
Hg oAc  ,H O
NaBH 4

(C) R  COOH 

NaOH
  R  
CH 3  I
 S

(D) 1  Butyne   T    U    V

NaNH 2 CH3  I 1 BH3 ,THF

 2  H O ,OH 2 2

32. The reaciton of (+) – 2 – iodobutane and NaI131 (I131 is radioactive isotope) in acetone was studied by

measuring the rate of racemisation (Kr) and the rate of incorporation of I131 is (Ki).

Me2CO

CH3CH·CH2CH3 + NaI131 CH3CH·CH2CH3

I I131

(+)–2–iodoctane

For this reaction, the relationship between Kr & Ki is :-

1 1
(A) Ki = 2 × Kr (B) Ki =   × Kr (C) Ki = Kr (D) Ki =   × Kr

2 3

33. Two isomeric SN2rip

sproducts are possible when sodium thiosulphate is allowed to react with one equivalent of

methyle
oniodide in methanol solution. In fact, only one of the two possible product is formed, which one is

formed ? Identify –

Oa Oon

(A) Na S – S a– O – CH3
+2
(B) CH3 – S – S+2– O– – Na

Oi O

(C) CH3 – O – S – S – O Na (D) CH3 – O – S – O Na

O O

34. Give the structure of nucleophile that could be used to convert the iodoethane into

CH3
CH3·CH2·S

H3C SK Me SK

(A) (B)

SK

Me
(C) (D)

Me SK

35. Identify the product "R" in th given reaction

CH 3 – – S – Cl O

O CH3 – C – ONa Hydrolysis

[P] [Q] H+/H2O

[R]

OH

OH OH Cl OAc

(A) (B) (C) (D)

36. KI in acetone, undergoes SN2 reaction with each of P, Q, R and S. The rate of reaction vary as :-

Cl

CH3Cl Cl
Cl

(P) (Q) (R) (S)

(A) P > Q > R > S (B) S > P > R > Q (C) P > R > Q > S (D) R > P > S > Q

37. Which of the following reaction is not possible –

(A) ROH + NaBr (B) ROH + HBr (C) R-Br + NaOH (D) R–Br + NaBr

EXERCIS-B

CH3 CH3

1. Ph CH C CH3 
EtOH
 [A], major

S
N1

Br

Identify the product [A] :

CH3 OEt

CH3 CH3 CH3

(A) Ph CH C CH3 (B)

CH3
OEt

CH3 CH3 CH3

CH3 CH3

(C) (D)

OEt OEt

2. Which one of the following compoundfs will be most reactive for SN1 reaction :-

I Cl Br Cl

O O O

(A) (B) (C) (D)

3. Arrange the following compounds in order of decreasing rate of Hydrolysis for SN1 reaction :-

H3C
CH2Br CH3 CH2Br CH3CH2 CH2Br CH CH2Br

H3C

(I) (II) (III) (IV)

(A) II > III > IV > I (B) IV > III > II > I (C) III > IV > II > I (D) I > II > III > IV

4. In the given reaction,

Cl

Cl

CH3OH
[x]

O Cl

Cl Cl Cl OCH3

Cl Cl OCH3 Cl
(A) (B) (C) (D)

O OH O OCH3 O Cl O Cl

5. Among the Bromides 1-3 given below, the order of ractivity in SN1 reaction is :-

Br Br
Br

(1) (2) (3)

(A) 3 > 1 > 2 (B) 3 > 2 > 1 (C) 2 > 3 > 1 (D) 2 > 1 > 3

6. Which of the following compound is most rapidy hydrolysed by SN1 mechanism :-

Cl

Cl

(A) (B) Cl (C) C Cl (D)

7. Which are possible products(s) in given reaction :-

CH3


Moist Ag 2 O
S 1
CH2Cl N

CH3

CH2OH
CH3 CH3

(A) (B) (C) (D)

CH2OH V OH

OH

8. The following compound on hydrolysis in aqueous acetone will give :-

CH3 CH3 CH3

H2 O
CH3 O NO2

Me 2CO

H Cl CH3

CH3 CH3 CH3

CH3 O NO2

(K)

H OH CH3

CH3 CH3 CH3

(L)
CH3 O NO2

H CH3 OH

CH3 CH3 CH3

CH3 O NO2

(M)

OH H CH3

(A) Mixture of (K) and (L) (B) Mixture of (K) and (M)

(C) only (M) (D) only (K)

9. The major product of the following reaction is :-


RCH 2 OH
H  (anhydrous)

O

(A) a hemiacetal (B) an acetal (C) an ether (D) an ester

10. For the given reaction,

R1 R1

R C X   R C OH
H 2O
SN1

R2
R2

which substrate will give maximum recemisation?

Me Me

(A) C Br (B) CH2 CH C Br

Me Me

Br
Br

(C) C OCH3 (D) C NO2

OCH3

11. Consider the following reaction(s) :-

CH3

H2 O

CH Br Reaction-I

CH3

H2 O
CH Br Me2CO Reaction-II

Identify the correct statement :-

(A) I give more % of racemisation (B) II give more % of recemisation

(C) I give more % of inversion products (D) II give more % of inversion products

CH3

SN1
12. CH Br Maximum recemisation takes place when :-

(A ) 100% H 2O (B) 100% Acetone

(C) 80% H2O + 20% Acetone (D) 80% Acetone + 20% H2O

13. The hydrolysis of ether [X] shown below :-

OR 
Acid
 OH + ROH

Correct statement for the above hydrolysis is :-

(A) NOT possible when pH is more than 7

(B) Slower when one phenyl replaces by p-nitro phenyl.

(C) NOT possible when R replaced by phenyl group

(D) Faster when one phenyl replaced by p-methoxy phenyl group.

14. Which of the following doubly allylic alkyl halide is solvolytically inert :-

CH2

(A) (B) (C) (D) All

H Br

Br
H Br

15. Consider the following bromides :-

Me Me

Me Br Me

Br Br

(M) (N) (O)

The correct ordeer of SN1 reactivity is :-

(A) M > N > O (B) N > O > M (C) N > M > O (D) O > N > M

16. SN1 reaction is feasible in :-

(A) Cl + KOH(aq) (B) Cl + KOH(aq)

(C) CH2CH2Cl + KOH(aq) (D) Cl + KOH(aq)

17. Choose the incorrect statement about the following reactions :-

Cl

Cl


CH3OH
SN1 [P] 
CH3OH
SN1 [Q]

(A) Both reactions proceed through a carboacation intermediate.

(B) The same mixture of products would be anticipated for both reactions.

(C) Rates of both raction smust be identical.

(D) Equatorial chloride is more stable than the axial chloride.

18. Choose the incorrect statement about the following SN1 reaction :-

80% Me2CO

Cl 20% H2O OH

(A) Increasing the percentage of more polar solvent, H2O, will increase the rate of the reaction.

(B) In the above reaction, t-butyl iodide will react at a faster rate than t-butyl chloride.

(C) Adding one equivalent of I– nucleophile will increase the rate of SN1 reaction.

(D) Increasing temperature will increase the rate of reaction.

19. 
H2O

Cl CH3OH

Which of the following is an UNLIKELY product of the reaction above?

OH

HO CH3O
(A) (B) (C) (D)

OCH3

20. The compound that undergoes solvolysis in aq ethanol most eaisly is :-

Me

Me

(A) Me Cl (B)
Me i Me Cl

Cl

(C) (D) Me Cl
Me

21. The order of decrasing rate of solvolysis with aqueous ethanol (Fastest  slowest) for the following bromides

is :-

Br CH3
CH 3 CH3

CH2
Br Br H3C CH3

(I) (II) (III)

(A) II > I > III (B) I > II > III (C) II > III > I (D) I > II > III

22. Choose the statement that is incorrect

(A ) M any SN2 reactions are slowest in protic (Hydroxylic) solvents

(B) SN2 reactions are the slowest in aprotic (non-hydroxylic) sovlents.

(C) SN1 reactions are subject to large solent effects.

(D) SN1 reactions are favoured by polar protic (hydroxylic solvents)

23. In the SN1 solvolysis of the following primary alkyl chlorides in aqueous ethanol, the order of decreasing

reactivity is :-

Cl Cl O Cl F F
Cl

H3C
, ,
H3C
, H3C

(I) (II) (III) (IV)

(A) I > II > III > IV (B) II > I > III > IV (C) IV > III > II > I (D) III > II > I > IV

24. A hydrocarbon with the formula C6H14 gives a mixuture containing only two mono-chlorides in photochemical

chlorination. One of these compounds solvolyzes very slowly, the hydrocarbon is :-

H3 C CH3 H3C CH3

(A) (B)
H3 C CH3 H3C

H3C CH3

(C) H3C (D) H C CH3

H3C 3

25. The rate of SN1 reaction in ethanol of the following substrates decreases in the order of

PhCH2OTs OTs CH3OTs EtOTs

(I) (II) (III) (IV)

(A) III > IV > I > II (B) II > I > IV > III (C) IV > III > II > I (D) I > II > IV > III

26. The following chlorides undergo solvolysis in ethanol.

Ph
Me Ph

Ph Cl , Ph Cl , Ph Cl , Ph Ph Cl

(I) (II) (III) (VI)

Find the correct relative rate (SN1)

(A) III > II > I > IV (B) IV > III > II > I

(C) II > III > I > IV (D) II > III > IV > I

H OH  

27. 
TSCl
Pyridine  A  
Bu 4 N.ACO
DMF  B 
NaOH
H 2O
 Product [X]

(+) – (S) – Sec-butanol

H OAc AcO H HO H

(A) (B) (C) (D)

HO H

28. Rate of solvolysis of alkyl chlorides in 50% aq. ethanol

Cl , Cl , Cl , Cl , Ph Cl

(P) (Q) (R) (S) (T)

(A) S > T > P > R > Q (B) T > S > P > R > Q

(C) P > T > Q > R > S (D) P > S > T > R > Q

29. Which of the following is "false" regarding SN1 reaction

(A) It would be faster at 25°C than 50°C

(B) It would be faster in ethanol than in pentane

(C) Keeping the moles of reactants constant but doubling the quantity of solvent would decrease the rate by

a factor of 4.

(D) Stereochemical inversion occurs exclusively.

30. The correct order of rate of solvolysis for the following compounds is :-

Br
Br

Br

(I) (II) (III)

(A) III > II > I (B) II > I > III (C) III > I > II (D) II > III > I

EXERCISE-C

1. The major product of the following reaction :

Br

(1) Ag2CO3/CH2 Cl2

(2)

OH

OAc

(A) (B)

OAc OAc

O O

(C) (D)

OAc OAc

2. Optically pure isomers A and B were heated with NaN3 in DMF. The correct statements from the following is:-

NMe2 NMe2 NMe2 NMe2

Br Br N3 N3

(A) (B) (C) (D)

(A) A gives optically pure D and B gives optivally pure C.

(B) A gives racemic mixture of C and B gives optically pure C.

(C) A gives optically pure C and B gives racemic C.

(D) A gives optically pure D and B gives racemic D.

3. Find the correct answer of following reaction regarding products :-

Me

OTs

OTs AcOH
M Product(s)

Me

(A) Pure enantiomer (100%) (B) Diastereomeric pair

(C) Recemic mixture (D) Enantiomeric excess

4. Find the correct answer of following reaction regarding products :-

Me

OTs

OTs AcOH
Product(s)
ma

Me

(A) Pure enantiomer (100%) (B) Diastereomeric pair

(C) Recemic mixture (D) Enantiomeric excess

Br

5. I- OH 
NaOH
 M

Br
OH  
Ag 2 O,H 2 O

II - NaOH
[N]

Find correct statements :-

(A) In Ist case Inversion take place (B) In IInd case Retention take place

(C) In Ist case Retention take placed (D) In IInd case Inversion take place

6. In the given reaction :

14
CH3 – CH2 – S – CH2 – CH2Br 
H 2O
 [X].

14
(A) CH3 – CH2 – S – CH2 – CH2Br (B) CH3 – CH2 – S – CH2 – CH2Br
14

not AA

(C) 1 : 1 mixture of A & B (D) 2 : 1 mixture of A & B

7. In the given reaction

CH3 – CH – CH2 – CH2 – CH – CH3 

(1) S H (1eq)
(2) KOH
[X]

OTs OTs

[X] will be :-

SH

(A) CH3 – CH – CH2 – CH2 – CH – CH3 (B) CH3 – CH – CH2 – CH2 – CH – CH3

OTs SH SH

CH3 CH3

(C) H3C CH3 (D) S

8. Solvolysis of the optically active compound [X], mainly gives :-

MeO Me

OTs  ?
AcOK

AcOH
Me

MeO Me MeO Me

(A) (B)

OAc OTs

Me Me

(Optically pure) (Optically pure)

MeO Me MeO Me

(C) (D)

oAc OAc

Me Me

+ +
(Enantiomer) (Enantiomer)

Br Br

9. Reaction-1 :
 
Trans

H

Br

OH Br

Br Br

 

Reaction-2 : 
H

Br
Trans

OH Br

In the both reaction trans-dibromide is formed as major product. Account for the overall rate of reaction in

both the cases :-

(A ) R1 > R2 (B) R2 > R1 (C) R1  R2 (D) can not compare

EXERCISE-D (SNAR)

One or more answer correct :-

NO2

1.

1 NaOH
  [A]
(2) H3O

Br

Product [A] is :-

NO2 NO2 OH NO2

(A) (B) (C) (D)

OH F F HO F

Br OH Br Br

2. Consider the following reactions :

Cl

I: 
KOH
 R1
O2N NO2

Cl

NO2

II : 
KOH
 R2

NO2

Cl

III : 
KOH
 R2

NO2 ie

NO2

Find the rate of reaction order :-

(A) R3 > R1 > R2 (B) R2 > R3 > R1

(C) R2 > R1 > R3 (D) R1 > R2 > R3

3. Most reactive toward SNAr –

Cl Br I
F

(A) (B) (C) (D)

NO2 NO2 NO2

NO2

Cl

NO2  

4. (1) NH 2  NH2

(2) KOH
 [R]

NO2

[R] is :-

NH–NH2

NO2

(A) Product [R] is (B) Product give colored compound with CH3CHO

NO2

(C) It is called as 2, 4–DNP. (D) SNAr reaction is bimolecular.

Cl
5. 
KSH
 [P], Identify [P] in this reaction :-

NO2

SH F SH Cl

Cl SH SH SH

(A) (B) (C) (D)

NO2 NO2 NO2 NO2

6. Which of the following is not resonance form of intermediate in nucleophilic addition of OH ion to p-

fluoronitrobenzene?

F OH F OH F OH F OH

0
(A) (B) (C) (D)

Or O O
– i
O O
–

7. Arrange the following compounds in increasing reactivity with CH3ONa –

F F F

NO2

NO2 O2 N NO2

NO2

(I) (II) (III)

(A) I < II < III (B) III < II < I (C) II < III < I (D) I < III < II

8. In addition elimination pathway of nucleophilic aromatic substitutions, –NO2 group is

(A) o, p-directing and Activating (B) o, p-directing and Deactivating

(C) m-directing and Activating (D) m-directing and Deactivating

9. Which chloroderivative of nitrobenzenes among the following would undergo hydrolysis, most readily with aq.

NaOH?

O2N NO2 NO2

(A) Cl (B) O2N Cl

NO2 NO2

O2N
O2 N

(C) O2N Cl (D) Cl

O2N O2N Cl

10. Which of the following is (are) true regarding intermediate in the addition elimination mechanism of the reaction

below?

F OMe


CH3ONa
 [Intermediate] 

NO2 NO2

(I) The intermediate is AROMATIC.

(II) The intermediate is resonance stable anion.

(III) e withdrawing group on benzene ring stabilise the intermediate.

(A) I only (B) II only (C) I and II (D) II and III

Exercise-E (Free Radical Substitution)

One of more than one

1. The reaction condition leading to the best yield of C2H5Cl are :-

(B) C2H6 + Cl2 (excess)  

Dark
(A) C2H6 (excess) + Cl2 
UV light


room temp.

(C) C2H6 + Cl2 (excess) 

UV light
 (D) C2H6 + Cl2 
UV light


2. Chlorination of toluene in presence of light and heat followed by treatment with aqueous NaOH gives :-

(A) O-cresol (B) p-cresol

(C) 2,4-dihydroxy toluene (D) Benzoic acid.

3. CH3 CH CH2 CH2 CH3 

Cl 2
hv

CH3

mono-chloro products [including stereo isomeres] are

(A) 6 (B) 7 (C) 8 (D) 9

4. Find the total number of optical acitve (chiral) monochloro product of given reaction :-


Cl2

hv

(A) 4 (B) 6 (C) 8 (D) 3

5. Find the total number of optically active (chiral) monochloro product of given reaction :-


Cl 2
hv

(A) 2 (B) 4 (C) 8 (D) 6

6. C4H8 (All cyclic isomers) 

Cl 2
hv
Dichloro product(s)

Find the total optically active product(s)

(A) 19 (B) 13 14 (C) 16 (D) 18

9
7. Find the number of fraction(s) obtained on fractional distillation of product mixture obtained on monochlorination

of given structure -

CH3

H Br 
Cl2

300 C

CH2CH3

(A) 4 (B) 10 (C) 5 (D) 8

8. Total number of possible trichloro prodeuct(s) obtained during photochlorination –

Me

H Cl
H Cl

Me

(A) 2 (B) 3 (C) 4 (D) 5

9. Pick the correct statement for mono-chloronation of (R)-sec-butylchloride –

Me

Cl H 
Cl2

300 C

Et

(A) There are four possible products; 3 are optically active 1 is optically inactive.

(B) There are five possible products ; 3 are optically inactive & 2 are optically active.

(C) There are five possible products ; 2 are optically inactive & 3 are optically active.

(D) There are four possible products ; 2 are optically active & 2 are optically inactive.

10. Find the total number of possible monobromo product(s) obtained in following given reaction :-


NBS


(A) 11 (B) 16 (C) 17 (D) 18

EXERCISE-F (SUBSTITUTION REACTIONS)

Compare rate of Solvolysis?

CH2Cl CH2Cl CH2Cl CH2Cl CH3

Cl CH3 C Cl

Cl , ,
1. 2. CH3

CH3 CH2CH3

3. 4. CH3 CH CH3 CH3 CH C CH3

Cl Cl Cl
Cl

I I I

5. (Ph)3C·Cl (Ph)2CH·Cl PhCH2Cl 6.

Cl Cl Cl

NH O

7. 8.

O Cl Cl

9. 10. CH2Cl CH2O Cl

O Cl N Cl

Que. Arrange the following in decreasing order of SN1 reactivity?

Cl , Cl
Cl , Cl ,

Cl , Cl , Ph

Cl

Que. Write the product of following SN1 reactions

CH3

1. CH3 C Cl 
aq. KOH
 2. Br 
H 2O


CH3

CH3

3. Cl 4.


EtOH
 
EtOH


Cl

Cl

5. MeOH 6. 
H 2O

O Cl

Cl Cl

7. Ph CH CH3  80% acetone

8. Ph CH CH3 
100% water

20% water

Me

EtOH
9. CH2 = CH – CH2Cl 10. Me C CH2Br 
H 2O


Me

11. Me CH CH CH2
EtOH
12. Me CH CH CH2 
C 2 H 5 OH


Cl Cl

Me Br Me Br

13. Me C CH Me 
H 2O
 (Major) 14. Me C CH Ph 
H 2O
 (Major)

Me Me

NH2

15. 
HNO 2
 A  B  C

 47%   48%   5% 

CH3

Br

16. 
H 2O
 17. CH3 O CH2Cl 
H 2O


CH3 CH3

18. CH3 C Cl 

CH3COOH
 19. C Br 
C2 H 5 OH


CH3 CH3

Que. : Compare the % of Racemisation?

(a) Ph CH CH3 

80% acetone
(b) Ph CH CH3 
20% H 2 O
100% H 2 O


Cl Cl

Que. : Compare % of Recemisation?

Br
Br

CH CH

(a) (b)

CH3O CH3 O2N Cl

Que : Tick () or ()

Compound SN1

1. Cl 2. CH2 = CH – Cl

3. CH3 – F 4.

Cl

CH3

5. CH3 C CH2Br 6. Ph – CH2Cl

Cl

7. CH2 = CH – CH2Cl 8. CH3 O CH2Cl

I
9. 10.

Cl

11. Ph C CH2Cl 12. Cl

Que. OH

OH

Que.

OH

H2 O
Que.  OH

If 2 Reso struct of cation, they exist as Reso. Hyb. So "Nu" attack from less Hindered site.

OH
HBr

Que.

If 2 structgure difference cation, then "Nu" attack at more stable cation.

Que.
HBr
OH

Que. OH HBr

OH HBr
Que.

EXERCISE - G

H F + NaI

(1) Br H acetone (2) Reactant 

C2 H5I
 S – CH2CH3
(one

mole) H3 C

Cl O O
CH2Cl PhSNa H3C S Cl

O
H3 C O–S– – CH3

(3) (4) Reactant O

H

NaN3
Ethanol-water

Product

O OH

(i) KOH C2H5O

–

(5) NH (6) + C2H5I

(ii) Br – – CH2Cl anhyd. C2H5OH

I CH3

Me H
(7) Et D 
KSH
 (8) H Cl 
NaI

Acetone

H Ph

Ph

N SOCl2

(9) + SoCl2 (10) D OH Pyridine

HO H
CH3

CH3 CH3

NaI

(11) H
SOCl2
(12) H Acatone
Ph Py Ph

Br
OH

Br
CH3

H Br NaCN

(13) 
KSH
 (14) H C H DMSO, 25°C
3

CH2CH3

Cl

CH2Cl H3C

KSH PhSNa

(15) (16) DMSO

Br

(18) Br CH2·Cl
NaCN
(17) OH  
(i) KH
ethanol

(ii) Ph·CH·Br

CH3 O

(i) Cl – S – – CH 3 CH2·Cl

OH
O

(19) +
(ii) Li Cl
–
(20) PhSK

DMSO

Br

Br

Cl

NaI
LiBr (Acetone)
(21) Acetone (excess) (22)

Br

Cl

OH

OH
NaH
[M] CH 3I
[N]

(23)  1. NaH

2. 1-Bromobutane, DMSO (24)

OH

TsCl
[P] CH 3ONa
[Q]

SH

(25) 
(i) 2NaNH 2


(ii) C2 H 5 I 1 mole 
(iii) H

OH

CH3
Cl – S – – CH3

(26)  Major product

1. BH3 I
O


2. OH, H 2O2

OH CH3 – – S – Cl O

(27) CH3 – C – O OH
O

[P] [Q] [R]

CH3

Me Br

Me
F

 
i Na
(28) PhSNa
(29) H OH  ii  CH3  Br SN2

dimethyl formamide

Et
NO2

Me Me

(i) PCl5

(30) H OH 
 ii  CH3ONa
(i) TsCl
 S N2 (31) H OH SN2
(ii) CH3ONa

Et Et

Ether with HI

CH3

1. CH3 O C CH3 

Conc.
HI
 2. CH 3  O – C 2 H 5 
conc. HI

CH3

3. O CH3 
Conc. HI
 4. CH2 O CH3 
Conc. HI


CH3

5. O 
Conc. HI
 6. CH O CH3 
Conc. HI


CH3

7. O 8. 
Conc. HI

O

9. O 
Conc. HI
 10. CH2 O 
Conc. HI


11. O 
Conc. HI
 12. O 
Conc. HI


13. O 
Conc. HI
 14. Ph – O – Et 
Conc. HI


15. CH3 – O Conc. HI 16. Ph – OH 

Conc. HI


Anhyd. HI

17. CH3CH2OH 

Conc. HI


Calculate no. of moles of HI

1. Ph  O  CH 3 
'x ' HI
 2. Ph  O  C 2 H 5 
' x ' HI


OCH3

3. 
'x ' HI
 4. O OCH3 
'x ' HI


OCH3

5. 6. Et – O – Et 
'x ' HI


'x ' HI


7. 8. CH3CH2CH2 – O – CH2
CH2 O 
'x ' HI
 
'x ' HI


OPh

OPh
OCH3

9. 10.

'x ' HI
 
'x ' HI


OPh

OCH3

11. 
'x ' HI


OCH3
OPh

Free radical Substitution

1. Draw the structure of major monohalo product in each of the following reactions :

CH3

CH2CH3

(A) 
Br2
 (B) Br2


Heat
hv light
or O2 N

UV light

(C) 
Br2
 (D) 
Br2

hv

Heat
or
UV light

(E) 
Cl2
hv
(F) 
NBS
hv


CH3

(G) 2 
(1) Cl excess hv
 
(2) aq. KOH

EXERCISE-H

Comprehension -1

Br OCH3 OCH3

+ CH3OH +

Ph Me Ph Me Ph Me
(+) (–) (+)

This reaction takes place by both SN1 and SN2 mechanisms. 60% of (+) – 1 – Bromoethyl benzene reacts by

SN1 and 40% of (+) – 1 – Bromoethyl benzene reacts by S N2.

1. The product mixture obtained after the reaction is

(A) dextro-rotatory (B) levorotatory (C) optically inactive (D) can not predict

2. What is the ratio (R/s) of both optically active ethers formed –

(A) 2 : 5 (B) 3 : 7 (C) 7 : 3 (D) 5 : 2

Comprehension - 2

CH3 NK

NBS O
[M] CH3 OH
[N]

Br

3. Structure of [M] is

CH3 Br CH3

Br

(A) (B) (C) (D) A & C both

Br

NH2 Br Br

4. Stucture of [N] is :-

CH3 CH2NH2

CH2NH2

(A) (B) (C) (D) None

Br

NH2 CH3

Comprehension–3

Four bottles, each contain a different Bromide, A,B,C,D, unfortunately, the label;s fell off and it is difficult to

know which bottle contains which compound. Compounds A,B,C,D were individually treated in two different

reactions. The results are summarized in the table below :-

Br

Br Br Br

[A] [B] [C] i [D]

Reaction – 1 : 
NaI
Acetone

Reaction – 2 :  
Ethanol

H2O

Results of Reaction-1 Results of Reaction-2

Bottle-1 No Reaction Rapid reaction that gives HBr

Bottle-2 Does not react at room temperature. Reacts slowly to give HBr

Reaction upon heating to give NaBr ppt.

Bottle-3 Reacts within 5 minutes at room No reaction

temperature to give NaBr ppt

Bottle-3 Reacts within several hour at room No reaction

temperature to give NaBr ppt

Give correct answer, Remember that each bottle contains a different bromide :-

5. Which compound is in bottle – 1?

(A) A (B) B (C) C (D) D

6. Which compound is in bottle-2?

(A) A (B) B (C) C (D) D

7. Which compound is in bottle-3?

(A) A (B) B (C) C (D) D

8. Which compound is in bottle-4?

(A) A (B) B (C) C (D) D

EXERCISE-I (SN1 – SN2 BASIC)

1. Which SN2 reaction is expected to be fastest?

(A) NaSH (B) NaSH

Br Br

2. Which SN1 reaction is expectd to be fastest?

(A)
CH3CH2OH
(B)
CH3CH2OH

Cl Cl

3. Which SN1 reaction is expected to be fastest?

(A) Br 
CH3OH
(B) Br 
CH3OH

4. Which reaction is faster A or B?

Cl + NaN3 ethanol N3 + NaCl

(A)

ethanol
I + NaN3 N3 + NaI

(B)

5. What is the mechanism of reaction in Qus-4?

(A) SN1 (B) SN2

6. Which reaction is faster A or B?

H2 O

(A) + HBr (B) Br H2O OH + HBr

Br OH

OH
7.
What is the mechanism in Que-6?

S1
(A) (B) SN2

8. Which reaction is faster A or B?

Br + NH3
Ethanol NH3 + Br
(A)

Ethanol NH3 + Br

Br + NH3
(B)

9. What is the mechanism in Que-8?

(A) SN1 (B) SN2

10. Which reaction is faster A or B?

(A) H2O (B) CH3COOH

Cl OH
+ HCl
Cl OAc
+ HCl

11. What is the mechanism in Que-10?

(A) SN1 (B) SN2

Rate of SN1 :

Rates of solvolysis of alkyl chlorides in 50% aqueous ehtanol at 44.6 °C

Compound Relative rate Comments

0.07 primary chloride : probably all SN2

Cl

0.12 secondary chloride : can do SN1 but not very well

Cl

2100 tertiary chloride : very good at SN1

Cl

1.0 primary but allylic : SN1 all right

Cl

Cl 91 allylic cation is secondary at one end

130000 allylic cation is tertiary at one end : compare with 2100 for

Cl

7700
simple tertiary

Rate of SN2 :

Rates of SN2 reaction of alkyl chlorides with the iodide ion

Compound Relative rate Comments

Me –– Cl 200 least hindered alhyl chloride

Cl
0.02 secondary alkyl chloride : stops because of stero hidradide

Cl 79 allyl chloride accelerated by a conjugation in transition state

Cl

200 benzyl chloride slightly more reactive than aliyl benzene ring

better at  conjugation isolated double bond.

Me 920 conjugation with oxygen ione pair accelerates reaction

O Cl

Cl

100000 conjugation with carbonyl group match more efective than

with simple alkyne or benzene ring. These d-carboxy halides

are the most reactive on all

* Relative rate of reaction of (Nu) with MeBr in ethanol :

PhS– > I– > CN– > Et3N > NH2–NH2 > NH2OH > –OH > CH3O– > PhO– > N3– > Me2S > Cl– >

CH3COO– > F– > NO3–

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