Chem 212
Alkyl Halide Problems 2
a)
Br
1. Provide the products, reagents or starting materials needed for the following reactions, show all stereochemistry.
2. Identify whether the reaction goes by an SN2 or an SN1 mechanism.
NaI
acetone
Br
I)
I
I
NaI
H2O
+
SN1
I
S N2
Br
b)
c)
NaN3
DMSO
Br
H
OMs
d)
H2O
SN1
NaCN
DMSO
SN2
j)
SN2
NaCN
DMF
Br
SN2
N3
OH
H
NaBr
acetone
CN
Br
k)
H I
SN2
NC H
SN1
NaBr
H2O
l)
Cl
NaBr
H2O
e)
TsO
Br
SN1
Br
NaI
H2O
m)
Cl
f)
NaI
acetone
Br
I
H OMs
SN2
SN1
I
H Br
NaBr
acetone
n)
MsO H
Br H
H2O
g)
Br
OH
SN1
MeOH
o)
SN1
Br
NaBr
H2O
h)
p)
SN1
OMe
TsO
NaH
OH
O
SN2
Br
OTs
3. Give the indicated rankings for the following. Provide explainations for your rankings
e) Fastest SN1 reaction
a) Fastest SN2 reaction with NaI in acetone
Br
Br
Br
Br
fastest
NaI
acetone
b) Fastest SN1 reaction with NaI in water
Br
Br
fastest
faster
Br
NaI
water
faster
c) fastest SN2 reaction
slower
g) fastest reaction with NaSH
NaI
Br acetone
I
faster
NaI
Br hexane
slower
I
Cl
Br
slowest
O
NaCN
NaOH
NaBr
best
about the same
i) best nucleophile
OH
best
NaI
best
I
fastest
h) best Nucleophile
d) best solvent for a SN2 reaction
I
f) fastest SN1 reaction
Br
slowest
Br
slower
slowest
Br
I
NaI
water
NaBr
NaF
worst
NaI
water