Preparation of t-butyl chloride(2-chloro-2-methylpropane)
CCH3
CH3CH3
OHHCl
CCH3
CH3CH3
Cl + H2O
t-butyl alcohol t-butyl chloride
(CH3)3COH + HCl
(CH3)3CCl + H2O
Reaction Mechanism?
(CH3)3COH + H-Cl
(CH3)3COH2 + Cl + -
Leaving Group
(CH3)3C-OH2 +
(CH3)3C + H2O
Cation
(CH3)3C + + Cl-
(CH3)3CCl
C CH3
CH3
CH3
tert-Butyl Cation
+sp2 flat
p
2
Transition State
δ δ
Substitution
Nucleophilic
1 bondat a time
Increasing Stability
Main Reaction
Side Reaction
CCH3
CH3CH3
OHHCl
CCH3
CH3CH3
Cl + H2O
t-butyl alcohol t-butyl chloride
CCH3
CH3CH3
OHHCl
+ H2O
t-butyl alcohol
CH2CCH3
CH3
isobutylene
CH2CCH3
CH3
C
CH3
CH3CH3
CCH3
CH3CH3
Cl
E1 N
ProcedureShake t-BuOH with concentrated HCl
Separate layers
Wash saturated aqueous NaCl
Wash saturated aqueous NaHCO3
Dry
Distill
t-BuCl
Shake t-BuOH with HCl
NaHCO3 + HCl
CO2 + H2O + NaCl
Wash to remove excess HCl
Distill product
Cool receiver
Clamp joints
Yield Calculations
A + B CMW 100 100 200
Use: 10 g A 20 g B
Limiting Reagent
Theoretical Yield
Experimental Yield
A + B CMW 100 100 200
Cpd Mass MW Moles
A 10 g 100 0.10
B 20 g 100 0.20
Theoretical yield:0.10 moles x 200 = 20 g
Experimental yield (%):100 x wt product / 20
LimitingReagent
CH3CH2CH2CH2OH n-butyl alcohol
HBr
CH3CH2CH2CH2Brn-butyl bromide
RCH2OH + H+ RCH2OH2+
C
R
HHOH2Br
δ− δ+
transition state
RCH2Br
Substitution
Nucleophilic
2 bonds ata time