Chemistry (F.Sc.2) Chapter # 10 Exercise Solved- Malik Xufyan 03137355727

1. Malik Xufyan F.Sc.ll (Chemistry)
03137355727 Ch.No. 10 (Exercise)
www.onlychemistrydiscussion.blogspot.com
Chapter No.10: Alkyl Halides
Exercise
Q 5. Write down a method for the preparation of ethyl magnesium bromide in the
laboratory?
H3C-CH2-Br + Mg
ether
H3C-CH2-Mg-Br
Q 8. Using ethyl bromide as a starting material how would you prepare the
following compounds. Give also the inorganic reagents and conditions necessary to
carry out these reactions.
(a) n-Butane
H3C-CH2-Br + 2Na + Br-CH2-CH3
Ether
H3C-CH2-CH2-CH3 + 2NaBr
(b) Ethyl Alcohol
H3C-CH2-Br + KOH
Aqueous
H3C-CH2-OH + KBr
(c) Ethyl Cyanide
H3C-CH2-Br + KCN H3C-CH2-CN + KBr
(d) Ethane
H3C-CH2-Br + H+
+ Zn + Br H3C-CH3 + ZnBr2
(e) Ethene
H2C CH2 + KOH
H Br
Alcohol
H2C CH2 + KBr + H2O
(f) Propanoic acid
H3C-CH2-Br + Mg
ether
H3C-CH2-Mg-Br
H3C CH2
Mg Br + C O
Ether
H3C-CH2-C-O-MgBr
O
O
H-OH
H
H3C-CH2-C-OH
O
+ Mg
Br
OH
Propanoic acid
(g) Propane

2. Malik Xufyan F.Sc.ll (Chemistry)
03137355727 Ch.No. 10 (Exercise)
www.onlychemistrydiscussion.blogspot.com
H3C-CH2
-
-Mg-Br + H3C+
-Br- ether
H3C-CH2-CH3 + Mg
Br
Br
Q 9. What products are formed when the following compounds are treated with
ethyl magnesium bromide, followed by hydrolysis in the presence of an acid.
i. HCHO
H3C CH2
Mg Br + C O
Ether
H3C-CH2-C-O-MgBr
H-OH
H
H3C-CH2-C-OH + Mg
Br
OH
1-Propanol
H
H
H
H
H
H
ii. CH3CHO
H3C CH2
Mg Br + C O
Ether
H3C-CH2-C-O-MgBr
H-OH
H
H3C-CH2-C-OH + Mg
Br
OH
2-butanol
H3C
H
H3C
H
H
H3C
Acetaldehyde

3. Malik Xufyan F.Sc.ll (Chemistry)
03137355727 Ch.No. 10 (Exercise)
www.onlychemistrydiscussion.blogspot.com
iii. CO2
H3C CH2
Mg Br + C O
Ether
H3C-CH2-C-O-MgBr
O
O
H-OH
H
H3C-CH2-C-OH
O
+ Mg
Br
OH
Propanoic acid
iv. (CH3)2CO
H3C CH2
Mg Br + C O
Ether
H3C-CH2-C-O-MgBr
H-OH
H
H3C-CH2-C-OH + Mg
Br
OH
2-methyl-2-butanol
H3C
H3C
H3C
H3C
H3C
H3C
Acetone
v. CH3-CH2-CHO

4. Malik Xufyan F.Sc.ll (Chemistry)
03137355727 Ch.No. 10 (Exercise)
www.onlychemistrydiscussion.blogspot.com
H3C CH2
Mg Br + C O
Ether
H3C-CH2-C-O-MgBr
H-OH
H
H3C-CH2-C-OH + Mg
Br
OH
3-pentanol
H
H3C-CH2
H
H
H3C-CH2
H3C-CH2
vi. ClCN
H3C-CH2
-
-Mg-Br + CN+
-Cl- ether
H3C-CH2-CN + Mg
Br
Cl
Cyano chloride
Propane nitrile
Magnesium chloro
bromide
Q 12. How will you carry out the following conversions.
(a) CH4 CH3CH2COOH
CH4 + Br2
2H3C-Br + 2Na
H3C-CH3 + Br2
H3C-Br + HBr
H3C-CH3 + 2NaBr
H3C-CH2-Br + HBr
hv
hv
H3C-CH2-Br + Mg
ether
H3C-CH2-Mg-Br

5. Malik Xufyan F.Sc.ll (Chemistry)
03137355727 Ch.No. 10 (Exercise)
www.onlychemistrydiscussion.blogspot.com
H3C CH2
Mg Br + C O
Ether
H3C-CH2-C-O-MgBr
O
O
H-OH
H
H3C-CH2-C-OH
O
+ Mg
Br
OH
Propanoic acid
(b) CH3-CH3 (CH3-CH2)4N+
Br-
H3C-CH3 + Br2
hv
H3C-CH2-Br + HBr
NH3 + H3C-CH2
+
-Br- H3C-CH2-NH2 + HBr
Ethyl amine
H3C-CH2-NH2 + H3C-CH2
+
-Br- (H3C-CH2)2NH + HBr
Diethyl amine
(H3CCH2)2NH + H3C-CH2
+
-Br- (CH3CH2)3N + HBr
Triethyl amine
(H3CCH2)3N + H3C-CH2
+
-Br- (CH3CH2)4N+
Br-
Quarternary ethyl ammonium bromide
(c) CH2=CH2 CH2-CH2-CH2-CH2-OH

6. Malik Xufyan F.Sc.ll (Chemistry)
03137355727 Ch.No. 10 (Exercise)
www.onlychemistrydiscussion.blogspot.com
H2C=CH2 + HBr H3C-CH2-Br
H3C-CH2-Br + Mg H3C-CH2-Mg-Br
H3C-CH2
-
-Mg+
-Br + H2C-CH2
O
Ethylene
epoxide
ether
H3C-CH2-CH2-CH2-O-
-Mg+
Br
H+
-OH-
H+
H3C-CH2-CH2-CH2-OH + Mg
Br
OH
1-Butanol
Ether
(d) CH3-CH2-CH2-Cl CH3-CH=CH2
H3C-HC CH2 + KOH
H Cl
Alcohol
H3C-CH CH2 + KCl + H2O
1-Propene
(e) CH3COOH CH3CH2COOH
H3C-COOH H3C-CH2-OH
H3C-CH2-OH + HBr H3C-CH2-Br + H2O
H3C-CH2-Br + Mg
ether
H3C-CH2-Mg-Br
LiAlH4
H3C CH2
Mg Br + C O
Ether
H3C-CH2-C-O-MgBr
O
O
H-OH
H
H3C-CH2-C-OH
O
+ Mg
Br
OH
Propanoic acid