Haloalkanes And Haloarenes

Question 1

Preparation of halo alkanes  from alcohols 
ROH + HCl --ZnCl2-->?
ROH+ NaBr--H2SO4-->?
ROH--Red Phos./X2-->?
ROH+ PCl5-->?
ROH+S0Cl2-->?

Answer 1

ROH + HCl --ZnCl2-->RCl + H20
ROH+ NaBr--H2SO4--- >RBr + NaHS04+ H20
ROH--Red Phos./X2-->RX
ROH+ PCl5-->RCl + S02+ HCl
ROH+S0Cl2-->RCl+S02+HCl

Question 2

Preparation of halo alkanes from hydrocarbons steps ?

Answer 2

By free radicle Halogenation
CH3CH2CH2CH3–Cl2/UV light–>CH3CH2CH2CH2Cl+ CH3CH2CHClCH3
By electrophilic substitution
By Sandmeyer’s Rection
From Alkenes by addition of hydrogen halide and by addition of halogens.

Question 3

Finkelstein reaction

RX+NaI–Acetone–>?

Answer 3

RX+NaI–Acetone–>RI+NaX

Question 4

Swart's Reaction 
R-Br+ AgF---->?
R-Br+HgF2---->?
R-Br+CoF3---->?
R-Br+SbF3---->?

Answer 4

R-Br+ AgF—->RF
R-Br+HgF2—->RF
R-Br+CoF3—->RF
R-Br+SbF3—->RF

Question 5

Hunsdiecker Reaction

CH3COOAg+Br2–CCl4–>?

Answer 5

CH3COOAg+Br2–CCl4–>CH3Br+AgBr+CO2

Question 6

Reactions of Halo alkanes :
Hoffmann Ammonolysis
RBr–NH2–>?

Answer 6

RBr–NH2–>RNH2

Question 7

Reactions of halo alkanes :
Reaction with cyanides
R-Br–KCN–>?
R-Br–AgCN–>?

Answer 7

R-Br–KCN–>RCN+KBr

R-Br–AgCN–>RNC+AgBr

Question 8

Nucleophilic Substitution Reaction 
R-Br--KOH-->?
R-Br--KNO2-->? 
R-Br--AgNO2-->?
R-Br--R'COOAg-->?

Answer 8

R-Br–KOH–>ROH+KBr
R-Br–KNO2–>R-ONO+KBr
R-Br–AgNO2–>RNO2+AgBr
R-Br–R’COOAg–>R0C0-R’+ AgBr

Question 9

Reaction of Haloalkanes :
Elimination Reaction
R-CH2-CH(Br)-R’–alc.K0H–>?

Answer 9

R-CH2-CH(Br)-R’–alc.K0H–>R-CH=CH-R’

Question 10

Reaction of Haloalkanes :
By reduction
R-Br+H2–N2,573K–>?
R-I+HI–Red Phos, 420K–>?

Answer 10

R-Br+H2–N2,573K–>RH + HBr

R-I+HI–Red Phos, 420K–> RH + I2

Question 11

Reaction of Haloalkanes :
Wurtz Reaction
RX+ 2Na+ XR–Dry ether–> ?

Answer 11

RX+ 2Na+ XR–Dry ether–> R-R+ 2NaX

Question 12

Reaction of halo alkanes:
Wurtz Fittig Reaction
RX+ 2Na+ X-R’–dry ether–>?

Answer 12

RX+ 2Na+ X-R’–dry ether–> R-R’ + 2NaX

Question 13

Rection of Haloalkanes :
Reaction with magnesium
RX+Mg–Dry Ether–>RMgX

Answer 13

RX+Mg–Dry Ether–>RMgX

Question 14

Reaction of Haloalkanes :
Isomerisation
CH3-CH2-CH2-Cl–573K–> ?

Answer 14

CH3-CH2-CH2-Cl–573K–> CH3-CH(Cl)-CH3

Question 15

Preparation of Aryl halides:
Sandmeyer’s reaction
C6H5-(N2+)Cl–CuCl/HCl–>?
C6H5-(N2+)Cl- –CuBr/HBr–>?

Answer 15

C6H5-(N2+)Cl–CuCl/HCl–>C6H5-Cl+N2

C6H5-(N2+)Cl- –CuBr/HBr–>C6H5-Br+N2

Question 16

Preparation of Aryl halide:
By Halogenation of aromatic hydrocarbon
C6H6+Cl2–FeCl3,dark–>?

Answer 16

C6H6+Cl2–FeCl3,dark–>C6H5-Cl+HCl

Question 17

Preparation of Aryl halide:
By side chain Halogenation
C6H5-CH3+Cl2–383K,sunlight–>?

Answer 17

C6H5-CH3+Cl2–383K,sunlight–>C6H5-CH2Cl

Question 18

Preparation of Aryl halide:
Gattermann Reaction
C6H5-(N2+)Cl- –Cu,HCl–>?

Answer 18

C6H5-(N2+)Cl- –Cu,HCl–>C6H5-Cl + N2

Question 19

Preparation of Aryl halide :
By Balz shiemann reaction
C6H5-(N2+)Cl- —->?

Answer 19

C6H5-(N2+)Cl- —->C6H5-F

Question 20

Preparation of Aryl halide:
By formation of Iodo Benzene
C6H5-(N2+)Cl- –KI–>?

Answer 20

C6H5-(N2+)Cl- –KI–>C6H5-I +N2 +KCl

Question 21

Preparation of Aryl halide:
From Phenol
C6H5-OH+ PCl3—->?

Answer 21

C6H5-OH+PCl3—-> C6H5-Cl + HCL + POCl3

Question 22

Reaction of Aryl Halides:
Nucleophilic Substitution Reaction
C6H5-Cl–NaOH,H+–>?
(p-NO2)C6H4-Cl–NaOH,H+–>?

Answer 22

C6H5-Cl–NaOH,H+–>C6H5-OH

(p-NO2)C6H4-Cl–NaOH,H+–>(p-NO2)C6H4-OH

Question 23

Reaction of Aryl Halide:
Halogenation
C6H5-Cl+ Cl2–anhy. FeCl3–>?

Answer 23

C6H5-Cl+ Cl2–anhy. FeCl3–>(o-Cl)-C6H4-Cl+ (p-Cl)-C6H4-Cl

;para is major here

Question 24

Reaction of Aryl Halide:
Nitration
C6H5-Cl–HNO3–>?

Answer 24

C6H5-Cl–HNO3–>(o-NO2)C6H4-Cl +(p-NO2)C6H4+ Cl

Question 25

Reaction of Aryl halides:
Sulphonation
C6H5-Cl–conc H2S04–>?

Answer 25

C6H5-Cl–conc H2S04–>(o-SO3H)-C6H4-Cl + (p-SO3H)C6H4-C

;para one is major

Question 26

Reaction of Aryl halides :
Ulmann Reaction
C6H5-I+Cu powder—->?

Answer 26

C6H5-I+Cu—->C6H5-C6H5