Q.
1 The order of reactivity of alkyl halide in the reaction R–X + Mg RMgX is
(A) RI > RBr > RCl (B) RCl > RBr > RI
(C) RBr > RCl > RI (D) RBr > RI> RCl
Q.2 Br–CH2–CC–CH2–Br Mg
BrMg–CH2–CC–CH2–MgBr
( excess)
Et 2O
Product
The major product is:
(A) Br–Mg–CH2–CC–CH2–Br (B) Cyclobutyne
(C) —(CH 2 C C CH 2—
)n (D) CH2 = C=C=CH2
Q.3 On conversion into Grignard followed by treatment with ethanol, how many alkyl halides (excluding
stereoisomers) would yield 2-methyl butane.
(A) 2 (B) 3 (C) 4 (D) 5
Q.4 Which of the following reacts with Grignard reagent to give alkane?
(A) nitro ethane (B) acetyl acetone
(C) acetaldehyde (D) acetone
Q.5 How many litres of methane would be produced when 0.595 g of CH3MgBr is treated with excess of
C4H9NH2
(A) 0.8 litre (B) 0.08 litre (C) 0.112 litre (D) 1.12 litre
Q.6 How many litres of ethene would be produced when 2.62 g of vinyl magnesium bromide is treated with
224 ml of ethyne at STP.
(A) 0.224 litre (B) 0.08 litre (C) 0.448 litre (D) 1.12 litre
MgBr OH
Q.7 + A
O – Ph
(A) (B) (C) (D)
Q.8 In which of the following reactions 3°alcohol will be obtained as a product.
O
||
(A) MgBr (excess) + H C Cl
H
O
||
(B) PhMgBr (excess) + CH 3 C Cl
H
O O
|| ||
(C) CH3MgBr (excess) + CH 3 C O C CH 3
H
O
||
(D) CH3MgBr (excess) + Cl C O Et
H
NARAYANA IIT ACADEMY GRIGNARD REAGENTS [1]
1 X
equivalent Mg D O
Q.9
2
Y; Y is
ether
(A) (B) (C) (D) None of these
Q.10 Compounds are shown with the no. of RMgX required for complete reaction, select the incorrect option
(A) CH3COOC2H5 1
(B) CH3COCl 2
(C) HOCH2COOC2H5 3
(D) 4
Q.11 What will be the order of reactivity of the following carbonyl compounds with Grignard's reagent?
H H CH3 Me3C
(I) C=O (II) C=O (III) C=O (IV) C=O
H CH3 CH3 Me3C
(A) I > II > III > IV (B) IV > III > II > I
(C) II > I > IV > III (D) III > II > I > IV
OH
Q.12 Carbonyl compound (X) + Grignard reagent (Y) Me Ph
Et
X , Y will be
O O
|| ||
(A) Et C Ph , Me Mg Br (B) Me C Ph , Et Mg Br
O O
|| ||
(C) Me C Et , Ph Mg Br (D) Et C Ph , Et Mg Br
Q.13 (R) - 2-Bromooctane ( X
i ) Mg
( ii ) CO 2
( iii ) H
X is
(A) (B)
(C) A and B both (D) None of these
NARAYANA IIT ACADEMY GRIGNARD REAGENTS [2]
Q.14 In which one of the following reaction products are not correctly matched in
(A) RMgX + CO2
Carboxylic acid
( 2) H
(B) RMgX + C2H5OH Alkane
(C) RMgX + CH3CH2Cl Alkene
(D) RMgX + Cl O Ether
Q.15 The number of moles of grignard reagent consumed per mole of the compound
is:
(A) 4 (B) 2 (C) 3 (D) 1
Q.16 Select the correct statement:
(A) 1,4-dibromobutane react with excess of magnesium in ether to generate di-Grignard reagent.
(B) 1,2-dichlorocyclohexane treated with excess of Mg in ether produces cyclohexene.
(C) Vicinal dihalides undergo dehalogenation to give alkene when heated with Zn dust or Mg.
(D) 1,3-dichloropropane by treatment with Zn dust or Mg forms cyclopropane.
O
||
CH3 CCH3
2
Mg H
Q.17 CH3–CH=CH2 Br
Dry ether NH 4Cl
End product of above reaction is
CH 2
||
(A) CH 2 CH CH 2 C CH 3 (B) H 2C CH CH C CH 3
|
CH 3
OH
|
(C) H 2 C CH CH 2 C CH 3 (D) H 2C CH CH 2 CH CH 2 OH
| |
CH 3 CH 3
OEt
Q.18 MgBr + H – C OEt followed
product.
OEt H 3O
Ethyl ortho formate
O
||
(A) C CH 3 (B) CH2CH=O
(C) CH = O (D) CH CH 3
|
CH O
NARAYANA IIT ACADEMY GRIGNARD REAGENTS [3]
Br
Q.19 1 Product (s)
. Mg / ether
2. CH3CHCH 2CH 3. H3O
| ||
OH O
Select the product from the following
I: II : CH 3CHCH 2CH III :
| ||
OH O
(A) III (B) I, III (C) I, II (D) II, III
O
||
Q.20 C 2 H 5O C OC 2 H 5 2 A. Product A formed
CH 3MgBr
(A) is ethyl acetate
(B) further react with CH3MgBr/H2O+ to give acetone
(C) further react with CH3MgBr/H2O+ to give t-butyl alcohol
(D) Can give pinacol when treated with Mg followed by H2O
Q.21 Order of rate of reaction of following compound with phenyl magnesium bromide is:
O O O
|| || ||
Me C Cl Me C H Me C O Et
I II III
(A) I > II > III (B) II > III > I (C) III > I > II (D) II > I > III
Q.22 Select the correct order of decreasing reactivity of the following compounds towards the attack of
Grignard reagent
(I) Methyl benzoate (II) Benzaldehyde (III) Benzoylchloride (IV) Acetophenone
(A) II > III > I > IV (B) I > II > III > IV
(C) III > II > IV > I (D) II > IV > I > III
CH3MgX
Q.23 O
NH4Cl
Product is
(A) Enantiomer (B) Diastereisomer (C) Meso (D) Achiral
Q.24 Nucleophilic addition of Grignard reagent cannot occur in
O O O O
|| || || ||
(A) CH 3 C C CH 3 (B) CH 3 C CH 2 C CH 3
O O
|| || O
(C) CH 3 C CH 2 CH 2 C CH 3 (D)
O
NARAYANA IIT ACADEMY GRIGNARD REAGENTS [4]
CH 3CCH 2CH 2CH 2Cl 3 A, A is
CH MgBr
Q.25
||
O
CH 3
|
(A) CH 3CCH 2CH 2CH 2Cl (B) CH 3CCH 2CH 2CH 2CH 3
| ||
OH O
(C) (D)
O O
|| ||
Q.26 CH 3CCH 2 CH 2 COCH 2 CH 3 ( A, A formed in this reaction is
i ) CH 3MgBr ( one mol)
(ii ) H 3O
OH O O O
| || || ||
(A) CH 3CCH 2CH 2COCH 2CH 3 (B) CH 3CCH 2CH 2CCH 3
|
CH 3
CH 3 CH 3
| |
(C) (D) CH 3CCH 2CH 2CCH 3
| |
OH OH
Cl2 Mg CH CHO
Q.27 PhCH3 (A) (B)
3
(C)
h ether NH4 Cl
CH3
OH
| OH CH3 OH
CH2 – CH – CH3 CH3 |
CH – CH3 C – CH3
(A) (B) (C) (D)
CH CH3
HO CH3
Q.28 Select the correct order of reactivity towards Grignard reagent for nucleophilic attack.
O O
|| ||
(A) R C R > R C H
(B) Cl CH 2 C H > CH 3CH 2 C H
|| ||
O O
O O
|| ||
(C) CH 3 C O NO2 < CH 3 C O
O O
|| ||
(D) R C OR > R C NR 2
NARAYANA IIT ACADEMY GRIGNARD REAGENTS [5]
Q.29 In the reaction sequence:
(i ) CH MgBr / CuCl
3 (X) Major + (Y)
(ii ) H 2O / H
(X) & (Y) respectively are
OH CH3 OH
(A) , (B) ,
CH3
(C) , (D) ,
(2)
O OH
C
Q.30 O (3)
RMgX
(
2 moles)
H
H
(1)
S
C
CH
(4)
Deprotonation will occur from the following positions:
(A) 1,2 (B) 1,3 (C) any two positions (D) 1,4
HO OEt
2 CH3MgX
Q.31 NH4Cl
P1 + P2
Identify P1 & P2.
O HO Me
(A) CH4 (B) (C) (D)
O
Br
14
(B) 3 (C) gas
NaHCO
Q.32 Mg
(A) (
i ) CO 2
( ii ) H / H 2O
Product C is
(A) CO (B) 14CO2
(C) CO2 (D) A mixture of 14CO and CO
2 2
NARAYANA IIT ACADEMY GRIGNARD REAGENTS [6]
(i ) CH ONH
Q.33 2CH3MgBr ( 2
3
ii ) H
(A) CH3–O–NH–CH3 (B) CH3–NH–CH3
(C) CH3–NH2 (D) CH3–OH
O OH
Q.34 ( (A)
i ) CH 3MgBr
( ii ) H / H 2O
CH3
(A) The product is optically active
(B) The product contains plane of symmetry
(C) The product shows geometrical isomerism.
(D) The product shows optical isomerism.
Q.35 Which of the following is incorrect.
O
O
C ||
(A) Cl OC2H5
CH 3MgX
CH 3 C OC 2 H 5
(1eq )
O
OC2H5 ||
(B) CH3–C OC2H5
C 2 H 5MgX
CH 3 C OC2 H 5
(1 eq )
OC2H5
S S
|| ||
(C) CH3MgX + C = S H CH 3 C SH
3O
O O
|| ||
(D) CH3MgX + C = O H CH 3 C OH
3O
Q.36 Which reaction gives 1° aromatic amine as major product.
(A) Mg
NH
/ ether
3 (B) Mg
NH
/ ether
3
(C) Mg
NH
/ ether
3 (D) Hg
(
OAc) 2
Ph NH3 / NaBH 4
NARAYANA IIT ACADEMY GRIGNARD REAGENTS [7]
O
||
Q.37 CH3MgBr + CH2=CH C H H Product (1, 4 addition). It is
3O
OH
|
(A) CH 2 CH C H (B) CH 2CH CH CH 3
| |
CH 3 OH
(C) CH3CH2CH2CHO (D) none
Q.38 ( Product.
i ) PhMgBr
( ii ) NH 4Cl
Me
Products in this reaction will be
(A) Stereoisomers (B) Enantiomer (C) Diastereomers (D) Geometrical isomers
CH MgBr (1 eq.)
Q . 3 9
3 ?
The product is:
(A) (B) (C) (D)
Q.40 CH2 = C = O (
i ) Br2
C4H8O
( ii ) CH 3MgBr
( 2 equi )
(A) (B) (C) (D) All of these
RMgX 3 (A) NH
(B) will be
( i ) CH CN RMgX
Q.41 Cl
( ii ) NH 4Cl 4
(A) 1° ROH (B) 2° ROH (C) 3° ROH (D) Alkene
NARAYANA IIT ACADEMY GRIGNARD REAGENTS [8]
Q.42 CH3—CH—CH2 CH
3
MgCl
H 2O
O
(A) CH 3 CH CH 2 OH (B) CH 3 CH CH 2 CH 3
| |
CH 3 OH
(C) CH 3 CH CH 3 (D) HO – CH2 – CH2 – CH2 – CH2 – OH
|
CH 3
Q.43 The reaction of 1 mole each of p-hydroxy acetophenone and methyl magnesium iodide will give
O O
(A) CH4 + IMgO C—CH3 (B) CH3–O C—CH3
OMgI MgI
O
(C) CH3–C OH (D) CH3O C—CH3
CH3
+ Ph Mg Br
r1
Q.44 (i) Ph CH2 CH2 OH
O
(ii) + Ph Mg Br
r2
Ph CH2 CH2 CH2 OH
O
(A) r2 > r1 (B) r1 > r2 (C) r1 = r2 (D) r1 = 2r2
Q.45 How many moles of Grignard reagent will be required by one mole of given compound?
O
SH
HO C – OEt
C – Cl
CH2–CH2 O
Cl
(A) 7 (B) 6 (C) 8 (D) 5
Q.46 Consider the given organometallic compound.
(I) (CH3)2Hg (II) (CH3)2Zn (III) (CH3)2Mg (IV) CH3Li
The correct decreasing order of ionic character is
(A) I > II > III > IV (B) II > I > III > IV (C) I > III > II > IV (D) IV > III > II > I
NARAYANA IIT ACADEMY GRIGNARD REAGENTS [9]
O (i) CH3MgBr
|| + P
(ii) H3O
Q.47 CH3CH = CH C CH 3
(i) CuI,CH3MgBr
+ Q
(ii) H3O
OH O
| ||
(A) P is CH3CH = CH C Me Q is CH 3CH CH 2 C CH 3
| |
Me CH 3
O OH
|| |
(B) P is CH 3CH CH 2 C CH 3 Q is CH3CH = CH C Me
| |
CH 3 Me
(C) P is CH 3CH CH C(CH 3 ) 2 Q is (CH 3 ) 2 CHCH 2 C CH 3
| ||
OH O
(D) P is (CH 3 ) 2 CHCH 2 C CH 3 Q is CH 3CH CH C(CH 3 ) 2
|| |
O OH
For Q. No.48 to Q. No. 50
Consider the given reaction and answer the following questions
COOCH3
MeMgBr
Products
O OCH3 ( excess)
O SH
||
O
Q.48 No. of RMgX consumed in the reaction is
(A) 4 (B) 5 (C) 6 (D) 7
Q.49 How many product will be fromed in given reaction (excluding stereo)
(A) 2 (B) 3 (C) 4 (D) 5
Q.50 Which of the following reaction will give the same Hydrocarbon formed as one of the product in the
above reaction.
(A) EtMgBr + Me – OH (B) PhMgBr + Me – OH
(C) MeMgBr + Ph – OH (D) MeMgBr + CH3 – CHO
NARAYANA IIT ACADEMY GRIGNARD REAGENTS [10]
ANSWER KEY
RH R–OH
H
RSO 2 RH R2Cd RSH
S
HOH or ROH
OH R2Hg
2
or Ph–OH
R–C–SH
2 NH N
RCH 2
O2 ,H2 O
R–R
H
SO2,H
CdC 2
or R 3 or R
2 O,
O CS
l
O Hg
OH
NH
S,H
2 ,H
H2 R 2CH R Si Br
X
O,
R–
R–C–OH 4 2
R–CH2CH=CH2
H
CO HC SiCl
2 ,H
RCHO,H2O =CH 2
4
ClC H 2–CH
R–CH2–CH–Me O R–Mg–X PbR4 R–Mg–X
Me–CH-CH2, RCOR,H2O PbCl 2 ClCH2OR
RCH2OR
HO H2O R Cl
O HCO 3 CO CO
H2 Cl 2
O H 2, OEt H Zn
3O
OE
HC (½
-C t
Cl–
eq.) ,H2 O
CH 2
OO e
N,H
RCOO
CN
R–COOEt
2
Et q.)
Cl
R–CH2–CH2–OH R–CHO R2Zn
RC
t
OE
,H 2
I2
Br2
Et
O
RCO
(½
H
R2–C=O R2CHOH RCl R–CN
OH
O RBr R–I
R–C–R
R–C
R
R
Q.1 A Q.2 D Q.3 C Q.4 A,B Q.5 C
Q.6 C Q.7 A Q.8 B,C,D Q.9 D Q.10 A
Q.11 A Q.12 A,B,C Q.13 C Q.14 C Q.15 A
Q.16 A,C,D Q.17 B Q.18 C Q.19 C Q.20 C,D
Q.21 A Q.22 C Q.23 A Q.24 B,D Q.25 C
Q.26 C Q.27 A,B,C Q.28 B Q.29 B Q.30 A
Q.31 A,B Q.32 C Q.33 C,D Q.34 B,C Q.35 B
Q.36 B Q.37 C Q.38 A,C,D Q.39 D Q.40 A
Q.41 C Q.42 B Q.43 A Q.44 B Q.45 A
Q.46 D Q.47 C Q.48 C Q.49 C Q.50 C
NARAYANA IIT ACADEMY GRIGNARD REAGENTS [11]
