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Chem 342 • Organic Chemistry II
Need to know Reactions for Exam 02
Nucleophilic Aromatic Substitution
Cl
O2N
OH
NO2
O2N
NaOH
NO2
25 °C
NO2
Cl
NaOH
OH
H
340 °C
2500 psi
H
NO2
Oxidation of Aromatic Substituents
CH3
O
C
KMnO4
O
O
C
KMnO4
OH
OH
O
C
KMnO4
KMnO4
OH
No Reaction
Reduction of Aromatic Substituents
H2
NO2
Pd/C
NH2
Pd/C
H2
NO2
SnCl2
NH2
H3O+
Pt
2000 psi
O
H2
H2
Pd/C
Preparation of Alcohols and Ethers from Alkenes
Hydroboration
CH3
BH3
then
H2O2, OH-
OH
Oxymercuration
CH3 Hg(OAc) H O
2 2
then
Dihydroxylation
cis diol
CH3 OsO
4
CH3
H
then
halohydrin
CH3
CH3
OH
CH3
OH
OH
NaHSO3
CH3
OH
Br2, H2O
NaBH4
Br
O
O
CH3
Chem 342
O
H
MCPBA
Cl
CH3
O
CH3
OH trans diol
epoxide
OH
H3O+
page 1
Spring 2009
Preparation of Alcohols from Carbonyls
NaBH4 or LiAlH4
O
OH
+
then H3O
R1
R2
R2
LiAlH4
then H3O+
O
R1
R1
R1
OH
OR2
RMgBr
then H3O+
O
R2
R1
RMgBr
then H3O+
O
R1
HO R
R1
OR2
R2
OH
R
R1
R
Elimination of Alcohols
H2SO4
OH
OH
POCl3
pyridine
E1
E2
Substitution/Activation of Alcohols
SOCl2
HCl
OH
Cl
SN1
SN2
OH
p-TosCl
pyridine
Cl
PBr3
OH
SN2
OH
OTos
Br
Oxidation of Alcohols
Jones (CrO3, H+)
or PCC
OH
R1
O
R2
R1
OH
R2
O
Jones (CrO3, H+)
R1
R1
OH
OH
O
PCC
R1
R1
H
Williamson Ether Synthesis
OH
Na
O
O
NaH
R1
R2
R1
CH3-I
R2
R1
CH3
R2
Ether Cleavage Reactions
O
OH
CH3
HI
R1
Chem 342
R2
R1
+
R2
R
O
R
CF3CO2H
OH
+
CH3-I
page 2
Spring 2009
Epoxide Formation
CH3
CH3
MCPBA
O
CH3
Br2, H2O
NaH
OH
Br
Epoxide Opening
H3O+
OH
OH
NaOH
O
O
OH
OH
OH
HCl
O
O
RMgBr
then H3O+
OH
R
Cl
Cl
HCl
O
OH
Oxidations
O
CH3
KMnO4
OH
O
PCC
O
O
KMnO4
2
R
OH
R
OH
1) O3
2) Zn, AcOH
O
KMnO4
OH
2
H
O
O
+
H
OH
CrO3
H3O+
O
CrO3
H3O+
O
OH
R
H
O
R
OH
Jones Oxidation
Preparation of aldehydes and ketones by reduction including Gilman reagent
O
O
DIBAL
R
OCH3
Chem 342
then H3O+
R
O
H
R
O
R'2CuLi
Cl
page 3
R
R'
Spring 2009
Other Reactions of Aldehydes and Ketones
O
Ph
NaCN
H2O
H
HO
HO
heat
H
Ph
H+
O
CN
Ph
H
cyanohydrin
H3O+
C N
Ph
HO
N
+ R-NH2
O
C OH
H
HO
Ph
R
2)
H
O
+ H2O
1) LiAlH4
C N
HO
H3O+
Ph
R
H+
+ R2NH2
NH2
imine
N
H
R
+ H2O
enamine
NEED TO KNOW MECHANISM
Mechanism for Imine Formation
HA
O
H2N R
H O
H O
H
H
N
R
H
O
A
H
N
R
Hemiaminal
Up to here this
is identical to a
hydration with
amine as
nucleophile
instead of water
HA
N
R
H
N
H N R
A
imine
-H2O
R
H
H
O
H
N
R
resonance structures
NEED TO KNOW MECHANISM
Mechanism for Enamine Formation
O
HN R
R
H O
HA
H O
R
H
N
R
H
O
A
R
N
R
Hemiaminal
HA
R
N
R
R
N
R N R
A
H
enamine
-H2O
R
H
H
O
R
N
R
resonance structures
The only difference is this last step. There is no proton on the
nitrogen to come off, so a proton is taken off of the alpha carbon
Chem 342
page 4
Spring 2009