Synthetic possibilities
Chem 315
Beauchamp
Reactions Study List Through Chem 315
For Use as a Study Guide
Beauchamp
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1
Synthetic possibilities
Chem 315
Beauchamp
2
Important acid/base reactions used in the examples below.
Base
Acid
Comments
New Base
sodium hydroxide
Na
O
C
R
H
O
O
O
H
Na
Ka(RCO2H)
Ka(H2O)
Keq =
R
-5
Keq = 10-16 = 10+11
10
carboxylic acids
Carboxylates are good
nucleophiles,
SN2 > E2 at Me, 1o and 2o RX
C
O
carboxylates
sodium hydride
Na
H2
C
R
H
O
H
Keq =
R
10-17 = 10+18
Keq =
10-35
alcohols
alkoxides are OK nucleophiles,
SN2 > E2 at Me and 1o RX, and
strong bases, E2 > SN2 at 2o
and 3oRX.
Na
H2
C
Ka(ROH)
Ka(H2)
O
alkoxides
sodium hydroxide
Na
H2
C
R
H
S
OH
Keq =
R
-8
Keq = 10-16 = 10+8
10
thiols
thiolates are good nucleophiles,
SN2 > E2 at Me, 1o and 2o RX,
and strong bases, E2 > SN2 at
3oRX.
Na
H2
C
Ka(RSH)
Ka(H2O)
S
thiolates
sodium amide
Na
R
C
C
H
terminal alkynes
NR2
Keq =
Ka(RCCH)
Ka(HNR2)
Keq =
10-25 = 10+12
10-37
R
C
Na
C
terminal acetylides are OK
nucleophiles, SN2 > E2 at Me and
1o RX, and strong bases, E2 > SN2
at 2o and 3oRX.
terminal acetylides
n-butyl lithium
H
Li
Li
n-Bu
N
N
Keq =
Ka(HNR2)
Ka(H-C4H9)
-37
Keq = 10-50 = 10+13
10
diisopropylamine
LDA is a very strong base that
is also very sterically hindered,
it always acts as a base in our
course.
LDA = lithium diisopropylamide
LDA = lithium diisopropylamide
O
Na
H
C
R
C
H2
ketones / aldehydes
Keq =
O
NR2
Ka(RCOCH3)
Ka(HNR2)
10-20 = 10+17
Keq =
10-37
C
R
CH2 Na
ketone enolates
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
enolates are good nucleophiles,
SN2 > E2 at Me, 1o and 2o RX,
and strong bases, E2 > SN2
at 3oRX.
Synthetic possibilities
Chem 315
Beauchamp
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LDA = lithium diisopropylamide
O
Na
C
R
H
O
Ka(ROCOCH3)
Ka(HNR2)
Keq =
C
R2
O
NR2
C
R
10-25 = 10+12
Keq =
10-37
ketones / aldehydes
CR2 Na
O
enolates are good nucleophiles,
SN2 > E2 at Me, 1o and 2o RX,
and strong bases, E2 > SN2
at 3oRX.
ester enolates
n-butyl lithium
Li
H
R
X
C
R
Keq =
PPh3
n-Bu
R
Ka(HCR2PPh3)
Ka(H-C4H9)
C
R
-33
Keq = 10-50 = 10+17
10
Wittig salt = ylid
PPh3
n-butyl lithium removes proton
from Wittig salt and makes a
good nucleophile at ketones and
aldehydes, forming alkenes.
betaine
n-butyl lithium
Li
S
S
Keq =
C
H
dithiane
n-Bu
Ka(dithiane)
Ka(H-C4H9)
-33
Keq = 10-50 = 10+17
10
H
S
S
C
Li
H
dithiane carbanion
n-butyl lithium removes proton
from dithiane and makes a
good nucleophile at RX compounds.
Can react once or twice in SN2
reactions. Sulfur acetal forms
carbonyl group after hydrolysis.
Makes aldehydes and ketones.
SN2 versus E2 choices at 2oRX.
At secondary RX (X= OTs, I, Br, Cl) SN2 and E2 products are in close competition with each other. Anions whose
conjugate acids have higher pKa’s (stronger bases have weaker acids) generally produce more E2 relative to SN2. The
two examples that we will emphasize at 2oRX centers are carboxlyates (SN2 > E2) vs hydroxide and alkoxides (E2 >
SN2), and cyanide (SN2 > E2) vs terminal acetylides (E2 > SN2). Steric hindrance in RX or the electron pair donor
also favors E2 > SN2.
Similar looking base/nucleophiles (used in our course) that react differently with 2oRX structures. (They all react by
SN2 at methyl and 1oRX and they all react by E2 at 3oRX.)
2o RX structures
Less basic, so SN2 > E2.
More basic, so E2 > SN2.
Less basic, so SN2 > E2.
More basic, so E2 > SN2.
O
N
C
R
C
C
cyanide
pKa of conjugate acid = 9
terminal acetylides
pKa of conjugate acid = 25
H
C
R
carboxylates
pKa of conjugate acid = 5
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
O
R
O
O
hydroxide and alkoxides
pKa of conjugate acid = 16-19
Synthetic possibilities
Chem 315
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Alkanes with Br2 / hν. (Synthesis of RX compounds, X = Br, Cl.)
Br2 / hν
CH4
H 3C
free radical
halogenation
achiral
free radical
halogenation
achiral
Br
Br2 / hν
Br
free radical
halogenation
enantiomers
(R and S)
Br
Br2 / hν
free radical
halogenation
Br
Br2 / hν
achiral
1. a. RX compounds with NaOH / H2O. (Alcohol synthesis.)
H3C
NaOH
H2O
Br
H3C
SN 2
OH
SN2
E2
Br
NaOH
H2O
OH
major enantiomers
(R and S)
minor
NaOH
H2O
Br
E2
NaOH
H2O
Br
achiral
OH
SN2
allylic and benzylic, very fast SN2 reactions
NaOH
H2O
Br
no reaction (vinyl and phenyl RX)
Forcing conditions can induce E2 reactions.
b. RX compounds with NaOR / ROH. (Ether synthesis, need to make RO--,Na+.)
H3C
SN 2
O Na
Br
O
SN 2
E2
Br
O
O Na
major enantiomers
(R and S)
minor achiral
Br
O Na
E2
SN 2
O Na
O
Br
allylic and benzylic, very fast SN2 reactions
no reaction (vinyl and phenyl RX)
Br
O Na
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Forcing conditions can induce E2 reactions.
Synthetic possibilities
Chem 315
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5
c. RX compounds with potassium t-butoxide (favors E2 > SN2).
K
H 3C
SN2
O
Br
O
E2
K
Br
O
enantiomers
(R and S)
K
Br
E2
O
SN2
K
O
Br
O
allylic and benzylic, very fast SN2 reactions
K
no reaction (vinyl and phenyl RX)
O
Br
Forcing conditions can induce E2 reactions.
d. RX compounds with sodium carboxylates. Ester synthesis (can hydrolyze with base to ROH and
RCO2H).
O
H3C
O
Na
Br
R
O
S N2
O
O
O
Br
Na
R
O
O
SN2 > E2
achiral
O
Br
Na
R
E2
O
O
O
S N2
Na
Br
R
O
O
allylic and benzylic, very fast SN2 reactions
O
Na
Br
R
O
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no reaction
Synthetic possibilities
Chem 315
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e. RX compounds with NaCN / DMSO. Nitrile synthesis.
H3C
NaCN
DMSO
Br
H 3C
C
S N2
N
SN2 > E2
NaCN
DMSO
Br
C
N
achiral
NaCN
DMSO
Br
E2
NaCN
DMSO
Br
S N2
C
N
NaCN
DMSO
Br
no reaction
f.
RX compounds with terminal acetylides (need to make). Alkyne synthesis at methyl and primary RX.
Na
H3C
Br
H 3C
R
R
mainly E2
Na
Br
S N2
R
enantiomers
(R and S)
Na
Br
E2
R
S N2
Na
Br
R
R
Na
Br
no reaction
R
g.
o
RX compounds with conjugate base of phthalimide (need to make). 1 RNH2 synthesis, after hydrolysis.
1.
O
Na
N
H3C
Br
O
2. NaOH
3. WK (neutralize)
1.
H3C
NH2
1. SN2
2. acyl hydrolysis
O
Na
N
1. SN2
2. acyl hydrolysis
NH2
Br
O
2. NaOH
3. WK (neutralize)
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
achiral
Synthetic possibilities
Chem 315
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O
1.
Na
N
Br
E2
O
2. NaOH
3. WK (neutralize)
1.
O
Na
N
Br
NH2
O
1. SN2
2. acyl hydrolysis
2. NaOH
3. WK (neutralize)
1.
O
Na
N
no reaction
Br
O
2. NaOH
3. WK (neutralize)
h. RX compounds with LiAlH4 (LAH). Nucleophilic hydride displaces “X” on carbon.
H3C
1. LiAlH4
2. WK
Br
Br
CH4
1. LiAlH4
2. WK
SN2
1. LiAlH4
2. WK
Br
not our
usual
mechanism
1. LiAlH4
2. WK
Br
1. LiAlH4
2. WK
Br
SN2
S N2
no reaction
i.
RX compounds with NaBH4. Nucleophilic hydride displaces “X” on carbon.
H3C
1. NaBH4
2. WK
Br
Br
1. NaBH4
2. WK
1. NaBH4
2. WK
Br
Br
1. NaBH4
2. WK
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
CH4
SN2
SN2
not our
usual
mechanism
SN2
Synthetic possibilities
Chem 315
Beauchamp
1. NaBH4
2. WK
Br
8
no reaction
j. RX compounds with enolates (need to make with LDA/-78oC). Alkylation of carbonyl compounds.
O
Li
H3C
Br
H2C
SN2
CH4
S N2
O
achiral
Li
Br
H2C
O
O
Li
Br
E2
H2C
O
O
Li
Br
SN 2
H2C
O
Li
no reaction
Br
H2C
k. RX compounds with water. Alcohol synthesis (rearrangements are possible).
H 3C
H2O
Br
no reaction
SN1 > E1
Br
Br
H2O
OH
SN1 > E1
OH
H2O
diastereomers
top & bottom
achiral
top = bottom
H2O
Br
Br
H2 O
SN1
no reaction
Br
l. RX compounds with alcohols. Ether synthesis (rearrangements are possible).
H3C
OH
Br
no reaction
SN1 > E1
Br
OH
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
O
diastereomers
top & bottom
achiral
Synthetic possibilities
Chem 315
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SN1 > E1
O
Br
OH
top = bottom
OH
Br
OH
Br
S N1
O
no reaction
m. RX compounds with liquid carboxylic acids. Ester synthesis (rearrangements are possible).
O
H3C
OH
Br
no reaction
SN1 > E1
O
O
OH
Br
diastereomers
top & bottom
achiral
O
O
O
Br
O
top = bottom
OH
O
Br
SN1 > E1
O
OH
SN1
O
O
no reaction
Br
OH
2. a. ROH with: SOCl2 or PCl3 or HCl or 1. TsCl/pyridine 2. NaCl. Synthesis of R-Cl.
given reagent
in the list
OH
OH
SN 2
SN 2
SN 2
SN 2
Cl
SN 1
SN 1
SN 1
SN 2
Cl
given reagent
in the list
SN1
SN1
SN1
SN1
given reagent
in the list
OH
Cl
OH
given reagent
in the list
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Cl
SN 1
SN 1
SN 1
SN 2
Synthetic possibilities
Chem 315
OH
Beauchamp
10
Cl
given reagent
in the list
SN2 or SN1
b. ROH with: PBr3 or HBr or 1. TsCl/pyridine 2. NaBr. Synthesis of R-Br.
given reagent
in the list
OH
OH
SN 2
SN 2
SN 2
Br
Br
SN1
SN1
SN2
given reagent
in the list
SN 1
SN 1
SN 1
given reagent
in the list
OH
Br
OH
OH
SN1
SN1
SN2
Br
given reagent
in the list
Br
given reagent
in the list
SN2 or SN1
c. ROH with: PI3 or HI or 1. TsCl/pyridine 2. NaI. Synthesis of R-I.
given reagent
in the list
OH
OH
SN 2
SN 2
SN 2
I
I
given reagent
in the list
SN1
SN1
SN2
given reagent
in the list
SN 1
SN 1
SN 1
OH
I
OH
OH
SN1
SN1
SN2
I
given reagent
in the list
I
given reagent
in the list
SN2 or SN1
d. ROH with: CrO3 / pyridine (PCC). Synthesis of aldehydes or ketones.
H
OH
CrO3 / pyridine
(PCC)
oxidation
O
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Synthetic possibilities
Chem 315
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OH
11
O
CrO3 / pyridine
(PCC)
oxidation
CrO3 / pyridine
(PCC)
no reaction
OH
OH
O
CrO3 / pyridine
(PCC)
oxidation
O
OH
CrO3 / pyridine
(PCC)
H
oxidation
e. ROH with: CrO3 / acid / water (Jones). Synthesis of carboxylic acids or ketones.
OH
CrO3 / acid / H2O
(Jones)
OH
oxidation
O
OH
O
CrO3 / acid / H2O
(Jones)
oxidation
CrO3 / acid / H2O
(Jones)
no reaction
OH
OH
CrO3 / acid / H2O
(Jones)
O
oxidation
O
OH
CrO3 / acid / H2O
(Jones)
OH
oxidation
f. ROH with acid chlorides. Synthesis of esters. (Need to make RCOCl with SOCl2 + acid.)
O
O
OH
R
acyl
substitution
Cl
R
O
O
acyl
substitution
O
OH
R
Cl
R
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O
Synthetic possibilities
Chem 315
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acyl
substitution
O
O
R
Cl
OH
R
O
O
acyl
substitution
O
OH
R
Cl
R
O
O
O
acyl
substitution
OH
R
Cl
R
O
g. ROH with sodium hydride, NaH. Synthesis of sodium alkoxides.
OH
Na
H
Na
H
acid/base
K
H
acid/base
OH
O
O
O
OH
OH
Na
H
OH
Na
H
acid/base
Na
Na
K
O Na
O Na
acid/base
acid/base
h. ROH with sulfuric acid / heat. Synthesis of alkenes (useful E1 reactions, rearrangement possible).
H2SO4 / ∆
OH
probably E2
OH
H2SO4 / ∆
E1
H2SO4 / ∆
E1
H2SO4 / ∆
E1
OH
OH
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Synthetic possibilities
Chem 315
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3. a. Alkenes with aqueous sulfuric acid. Alcohol synthesis (rearrangements are possible).
OH
H2SO4 / H2O
(H3O+)
hydration
achiral
hydration
OH
H2SO4 / H2O
(H3O+)
enantiomers
(R and S)
OH
hydration
H2SO4 / H2O
(H3O+)
enantiomers
(R and S)
OH
hydration
H2SO4 / H2O
(H3O+)
achiral
hydration
OH
H2SO4 / H2O
(H3O+)
achiral
hydration
H2SO4 / H2O
(H3O+)
S
OH
S
diastereomers
(SR and SS)
b. Alkenes with alcohol + sulfuric acid. Ether synthesis (rearrangements are possible).
OR
H2SO4 / ROH
(ROH2+)
H2SO4 / ROH
(ROH2+)
hydration
achiral
hydration
OR
enantiomers
(R and S)
OR
hydration
H2SO4 / ROH
(ROH2+)
enantiomers
(R and S)
OR
H2SO4 / ROH
(ROH2+)
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
hydration
achiral
Synthetic possibilities
Chem 315
Beauchamp
H2SO4 / ROH
(ROH2+)
14
OR
hydration
achiral
hydration
H2SO4 / ROH
(ROH2+)
OR
S
S
diastereomers
(SR and SS)
c. Alkenes with HX acid (HCl, HBr, HI). Synthesis of RX compounds.
Br
H
addition
Br
(or HCl or HI)
achiral
Br
H
addition
Br
(or HCl or HI)
enantiomers
(R and S)
Br
H
addition
Br
(or HCl or HI)
enantiomers
(R and S)
Br
H
addition
Br
(or HCl or HI)
achiral
H
Br
Br
(or HCl or HI)
addition
achiral
H
addition
Br
(or HCl or HI)
Br
S
S
diastereomers
(SR and SS)
d. Alkenes with Br2 or Cl2. Synthesis of vicinal dihalide (anti addition).
Br
Br
Br
(or Cl2)
bromination
Br enantiomers
R and S
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Synthetic possibilities
Chem 315
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Br
Br
bromination
Br
(or Cl2)
meso, RS
Br
Br
Br
Br
bromination
Br
(or Cl2)
enantiomers
RR and SS
Br
Br
bromination
Br
(or Cl2)
enantiomers
RR and SS
Br
Br
Br
bromination
Br
(or Cl2)
Br
achiral
Br
bromination
Br
Br
(or Cl2)
Br
S
diastereomers
SRR and SSS
e. Alkenes with Br2/H2O or Cl2/H2O. Synthesis of bromohydrin or chlorohydrin (anti + Markovnikov
addition).
anti + Markovnikov
addition
OH
Br2 / H2O
(or Cl2 / H2O)
Br
OH
enantiomers
R and S
anti + Markovnikov
addition
Br2 / H2O
(or Cl2 / H2O)
enantiomers
RS and SR
Br
anti + Markovnikov
addition
OH
Br2 / H2O
(or Cl2 / H2O)
Br
enantiomers
RR and SS
OH
Br2 / H2O
(or Cl2 / H2O)
Br
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
anti + Markovnikov
addition
enantiomers
RR and SS
Synthetic possibilities
Chem 315
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Br2 / H2O
(or Cl2 / H2O)
16
anti + Markovnikov
addition
OH
Br
achiral
Br
Br2 / H2O
(or Cl2 / H2O)
anti + Markovnikov
addition
OH
S
S
diastereomers
SRR and SSS
f. Alkenes with Br2/ROH or Cl2/ROH. Synthesis of bromo or chloro “ethers”.
anti + Markovnikov
addition
OR
Br2 / ROH
(or Cl2 / ROH)
Br
enantiomers
R and S
OR
anti + Markovnikov
addition
Br2 / ROH
(or Cl2 / ROH)
enantiomers
RS and SR
Br
OR
Br2 / ROH
(or Cl2 / ROH)
anti + Markovnikov
addition
Br
enantiomers
RR and SS
OR
anti + Markovnikov
addition
Br2 / ROH
(or Cl2 / ROH)
enantiomers
RR and SS
Br
anti + Markovnikov
addition
OR
Br2 / ROH
(or Cl2 / ROH)
Br
achiral
Br
anti + Markovnikov
addition
Br2 / ROH
(or Cl2 / ROH)
OR
S
S
g. Alkenes with 1. BH3
diastereomers
SRR and SSS
2. H2O2/HO--. Hydroboration/oxidation = anti-Markovnikov alcohols.
1. BH3
2. H2O2 / HO
OH
1. syn addition
2. oxidation
achiral
OH
1. BH3
2. H2O2 / HO
1. syn addition
2. oxidation
enantiomers
R and S
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Synthetic possibilities
Chem 315
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OH
1. syn addition
2. oxidation
1. BH3
2. H2O2 / HO
enantiomers
R and S
1. syn addition
2. oxidation
1. BH3
2. H2O2 / HO
achiral
OH
1. syn addition
2. oxidation
OH
1. BH3
2. H2O2 / HO
achiral
OH
1. syn addition
2. oxidation
1. BH3
2. H2O2 / HO
CH3
S
S
H
h. Alkenes with 1. BH3
diastereomers
SRR and SSS
2. Br2/CH3O--. Hydroboration/bromination = anti-Markovnikov R-Br.
1. BH3
2. Br2 / CH3O
1. syn addition
2. bromination
Br
achiral
Br
1. syn addition
2. bromination
1. BH3
2. Br2 / CH3O
enantiomers
R and S
Br
1. syn addition
2. bromination
1. BH3
2. Br2 / CH3O
enantiomers
R and S
1. syn addition
2. bromination
1. BH3
2. Br2 / CH3O
achiral
Br
1. BH3
2. Br2 / CH3O
Br
1. syn addition
2. bromination
achiral
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Synthetic possibilities
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Br
1. BH3
2. Br2 / CH3O
1. syn addition
2. bromination
CH3
diastereomers
SRR and SSS
S
S
H
i. Alkenes with 1. HgX2 / H2O 2. NaBH4. Alcohol synthesis with minimal rearrangements (Markovnikov).
OH
1. HgX2 / H2O
2. NaBH4
achiral
OH
1. HgX2 / H2O
2. NaBH4
enantiomers
R and S
OH
1. HgX2 / H2O
2. NaBH4
enantiomers
R and S
1. HgX2 / H2O
2. NaBH4
achiral
OH
1. HgX2 / H2O
2. NaBH4
OH
1. HgX2 / H2O
2. NaBH4
achiral
diastereomers
SR and SS
CH3
S
S
OH
j. Alkenes with 1. HgX2 / ROH 2. NaBH4. Ether synthesis with minimal rearrangements (Markovnikov).
O
1. HgX2 / CH3OH
2. NaBH4
1. HgX2 / CH3OH
2. NaBH4
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
achiral
O
enantiomers
R and S
Synthetic possibilities
Chem 315
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O
1. HgX2 / CH3OH
2. NaBH4
enantiomers
R and S
1. HgX2 / CH3OH
2. NaBH4
achiral
O
1. HgX2 / CH3OH
2. NaBH4
O
achiral
diastereomers
SR and SS
1. HgX2 / CH3OH
2. NaBH4
CH3
S
S
O
k. Alkenes with OsO4 or KMnO4. “Syn” synthesis of vicinal diols.
OsO4
or
OH
syn addition
KMnO4
OsO4
or
enantiomers
R and S
OH
OH
syn addition
KMnO4
enantiomers
RR and SS
OH
OsO4
or
OH
syn addition
OH
KMnO4
OsO4
or
meso
RS and SR
OH
syn addition
KMnO4
OsO4
or
KMnO4
OH
meso
RS and SR
OH
syn addition
OH
achiral
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
Synthetic possibilities
Chem 315
Beauchamp
20
OH
OsO4
or
syn addition
KMnO4
CH3
S
S
OH
diastereomers
SSR and SRS
l. Alkenes with 1. O3 / -78oC 2. CH3SCH3 or Zn. Synthesis of aldehydes or ketones.
O
1. O3 / -78oC
2. CH3SCH3
O
CH
H2C
H3C
O
1. O3 / -78oC
2. CH3SCH3
CH3
HC
CH
H3C
O
O
CH3
o
1. O3 / -78 C
2. CH3SCH3
HC
CH
H3C
O
O
C
H
H
C
o
1. O3 / -78 C
2. CH3SCH3
O
1. O3 / -78oC
2. CH3SCH3
O
O
H2C
O
C
H
1. O3 / -78oC
2. CH3SCH3
CH3
S
S
O
m. Alkenes with 1. O3 / -78oC 2. NaBH4. Synthesis of alcohols.
OH
1. O3 / -78oC
2. NaBH4
1. O3 / -78oC
2. NaBH4
OH
H3C
OH
OH
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
Synthetic possibilities
Chem 315
Beauchamp
21
OH
o
1. O3 / -78 C
2. NaBH4
OH
OH
o
1. O3 / -78 C
2. NaBH4
OH
1. O3 / -78oC
2. NaBH4
OH
OH
H3C
OH
diastereomers
(SR and SS)
o
1. O3 / -78 C
2. NaBH4
CH3
S
S
OH
n. Alkenes with 1. O3 / -78oC 2. H2O2 / HO--. Synthesis of carboxylic acids or ketones.
O
1. O3 / -78oC
2. H2O2 / HO
HO
O
C
C
H3C
OH
OH
O
1. O3 / -78oC
2. H2O2 / HO
C
H3C
OH
O
1. O3 / -78oC
2. H2O2 / HO
C
H3C
OH
CO2H
1. O3 / -78oC
2. H2O2 / HO
1. O3 / -78oC
2. H2O2 / HO
CO2H
HO
O
O
C
OH
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
Synthetic possibilities
Chem 315
Beauchamp
22
CO2H
1. O3 / -78oC
2. H2O2 / HO
CH3
S
S
O
o. Alkenes with meta chloroperbenzoic acid (mCPBA). Synthesis of epoxides.
O
Ar
H
(mCPBA)
O
syn addition
O
enantiomers
R and S
O
O
O
Ar
syn addition
H
(mCPBA)
O
enantiomers
RR and SS
O
O
O
Ar
syn addition
H
(mCPBA)
O
meso
RS and SR
O
O
syn addition
Ar
H
(mCPBA)
O
O
meso
RS and SR
O
O
Ar
(mCPBA)
O
syn addition
O
H
O
achiral
O
syn addition
Ar
H
(mCPBA)
O
O
S
O
S
diastereomers
SSR and SRS
p. Alkenes with CH2I2 / Zn (Simmons-Smith Rxn). Carbenoid synthesis of cyclopropanes.
syn addition
CHI2 / Zn(Cu)
Simmons-Smith
CHI2 / Zn(Cu)
Simmons-Smith
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
enantiomers
R and S
syn addition
enantiomers
RR and SS
Synthetic possibilities
Chem 315
Beauchamp
23
syn addition
CHI2 / Zn(Cu)
Simmons-Smith
meso
RS and SR
syn addition
CHI2 / Zn(Cu)
Simmons-Smith
meso
RS and SR
syn addition
CHI2 / Zn(Cu)
Simmons-Smith
achiral
syn addition
CHI2 / Zn(Cu)
Simmons-Smith
diastereomers
SSR and SRS
S
S
q. Alkenes with CHCl3 / RO-- or CHBr3 / RO--. Carbene synthesis of dihalocyclopropanes.
CHCl3 / NaOH
or
CHBr3 / NaOH
CHCl3 / NaOH
or
CHBr3 / NaOH
CCl2
syn addition
enantiomers
R and S
syn addition
CCl2
enantiomers
RR and SS
CCl2
CHCl3 / NaOH
or
CHBr3 / NaOH
syn addition
CHCl3 / NaOH
or
CHBr3 / NaOH
syn addition
CHCl3 / NaOH
or
CHBr3 / NaOH
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
meso
RS and SR
CCl2
CCl2
meso
RS and SR
syn addition
achiral
Synthetic possibilities
S
Chem 315
Beauchamp
24
syn addition
CHCl3 / NaOH
or
CHBr3 / NaOH
(haloform rxn)
CCl2
diastereomers
SSR and SRS
S
r.
Alkenes with Pd / H2. Synthesis of “alkane” from “alkene” (hydrogenation).
syn addition
Pd / H2
achiral
syn addition
Pd / H2
achiral
syn addition
Pd / H2
achiral
syn addition
Pd / H2
achiral
syn addition
Pd / H2
achiral
syn addition
Pd / H2
diastereomers
SR and SS
S
S
4. a. Alkynes with aqueous sulfuric acid (plus some Hg+2 catalyst). Synthesis via enols (Markovnikov addition).
O
H2SO4 / H2O
= H3O+ (Hg+2)
Markovnikov addition
(enol tautomerization
to keto)
O
Markovnikov addition
(enol tautomerization
to keto)
H2SO4 / H2O
= H3O+ (Hg+2)
H2SO4 / H2O
= H3O+ (Hg+2)
O
O
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
Synthetic possibilities
Chem 315
Beauchamp
25
O
H2SO4 / H2O
= H3O+ (Hg+2)
Markovnikov addition
(enol tautomerization
to keto)
b. HX addition to alkynes. Markovnikov addition.
H
Br
Br
Markovnikov
addition
(or HCl or HI)
H
Br
Br
Markovnikov
addition
(or HCl or HI)
H
Br
Br
(or HCl or HI)
Br
Br
H
Br
(or HCl or HI)
Markovnikov
addition
c. Bromination (or chlorination) of alkynes. Bridging bromonium ion.
Br2
Br
or
anti addition
Cl2
Br
Br2
Br
or
anti addition
Cl2
Br
Br2
Br
or
anti addition
Cl2
Br
Br
Br2
or
anti addition
Cl2
Br
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
Synthetic possibilities
Chem 315
Beauchamp
26
d. 1. Hydroboration 2. oxidation of alkynes (anti-Markovnikov addition makes aldehydes or ketones via enolate).
O
1. HBR2
2. H2O2 / HO
anti Markovnikov
addition
H
O
1. HBR2
2. H2O2 / HO
anti Markovnikov
addition
O
1. HBR2
2. H2O2 / HO
O
1. HBR2
2. H2O2 / HO
O
anti Markovnikov
addition
e. Catalytic hydrogenation reduces triple bond to “alkane”.
Pd / H2
Pd / H2
Pd / H2
Pd / H2
f. Catalytic hydrogenation with quinoline “poison” of Pd catalyst reduces triple bond to Z alkene (syn addition).
Pd / H2
quinoline
(Lindlar's Cat.)
Pd / H2
quinoline
(Lindlar's Cat.)
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
Synthetic possibilities
Chem 315
Beauchamp
27
Pd / H2
quinoline
(Lindlar's Cat.)
Pd / H2
quinoline
(Lindlar's Cat.)
g. Sodium metal + liquid ammonia reduction of triple bond to E alkenes.
Na / NH3
(liq - =33oC)
Na / NH3
(liq - =33oC)
Na / NH3
(liq - =33oC)
Na / NH3
(liq - =33oC)
h. Zipper reaction moves triple bond to terminal position where it can be removed to form sp carbanion nucleophile.
1. NaNR2
2. WK
Zipper reaction
1. NaNR2
2. WK
Zipper reaction
1. NaNR2
2. WK
Zipper reaction
1. NaNR2
2. WK
Zipper reaction
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
Synthetic possibilities
Chem 315
Beauchamp
28
i. Formation of conjugate base + addition of aldehyde electrophile forms propargyl alcohol.
OH
1. NaNR2
2. O
H
1. NaNR2
2. O
OH
H
OH
1. NaNR2
2. O
H
1. NaNR2
2. O
H
OH
j. Formation of conjugate base + addition of ketone electrophile forms propargyl alcohol.
1. NaNR2
2.
O
OH
1. NaNR2
2.
O
OH
1. NaNR2
2.
O
OH
1. NaNR2
2.
OH
O
k. Formation of conjugate base + addition of methyl or primary RX electrophile forms a longer alkyne.
1. NaNR2
2.
Br
1. NaNR2
2.
Br
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
Synthetic possibilities
Chem 315
Beauchamp
29
1. NaNR2
2.
Br
1. NaNR2
2.
Br
l. Formation of conjugate base + addition of secondary electrophile reacts in a nonproductive E2 reaction.
1. NaNR2
2. Br
E2 reaction
1. NaNR2
2. Br
E2 reaction
1. NaNR2
2. Br
E2 reaction
1. NaNR2
2. Br
E2 reaction
j. Formation of conjugate base + addition of epoxide electrophile forms an alkynyl alcohol via SN2
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
Synthetic possibilities
Chem 315
Beauchamp
30
reaction.
1. NaNR2
2.
O
R
R
OH
1. NaNR2
2. O
OH
1. NaNR2
2. O
OH
1. NaNR2
2.
O
R
OH
R
5.
a. Epoxides with aqueous hydroxide (followed by workup = neutralization).
NaOH
H 2O
O
HO
achiral
OH
2. WK
O
NaOH
H2O
R
HO
R
OH
chiral
2. WK
NaOH
H 2O
O
OH
OH
achiral
2. WK
S
R
O
S
S
OH
NaOH
H 2O
2. WK
S
S
diastereomers
b. Epoxides with alcoholic alkoxide (followed by workup = neutralization).
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
R
OH
R
OH
OH
S
Synthetic possibilities
Chem 315
O
Beauchamp
RO
/ ROH
31
HO
achiral
OR
2. WK
O
HO
RO
R
/ ROH
R
OR
chiral
2. WK
O
RO
OH
/ ROH
OR
achiral
2. WK
S
OR
R
O
/ ROH
2. WK
S
S
RO
S
S
R
OH
R
OR
OH
S
diastereomers
c. Epoxides with aqueous acid.
H2SO4 / H2O
(H3O+)
O
HO
achiral
OH
2. WK
O
H2SO4 / H2O
(H3O+)
R
S
OH
2. WK
OH
H2SO4 / H2O
(H3O+)
O
chiral
(inversion)
OH
achiral
OH
2. WK
S
OH
R
O
S
S
H2SO4 / H2O
(H3O+)
2. WK
S
S
diastereomers
d. Epoxides with alcoholic sulfuric acid.
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
R
OH
R
OH
OH
S
Synthetic possibilities
Chem 315
Beauchamp
H2SO4 / ROH
(ROH2+)
O
32
HO
achiral
OR
2. WK
O
S
H2SO4 / ROH
(ROH2+)
R
OH
2. WK
OR
H2SO4 / ROH
(ROH2+)
O
chiral
(inversion)
OH
achiral
OR
2. WK
OR
S
R
O
2. WK
S
S
H2SO4 / ROH
(ROH2+)
S
S
R
OH
R
OR
OH
S
diastereomers
e. Epoxides with cyanide (followed by workup = neutralization)..
NaCN
DMSO
O
HO
achiral
C
N
2. WK
O
NaCN
DMSO
R
HO
R
C
chiral
N
2. WK
O
N
OH
NaCN
DMSO
C
achiral
2. WK
N
R
O
S
S
S
NaCN
DMSO
2. WK
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
C
and SRR
S
S
OH
diastereomers
Synthetic possibilities
Chem 315
Beauchamp
33
f. Epoxides with terminal acetylides (followed by workup = neutralization).
Na
O
HO
R
achiral
2. WK
R
Na
O
HO
R
R
R
chiral
2. WK
R
R
Na
O
OH
R
achiral
2. WK
R
R
Na
O
S
S
S
and SRR
R
2. WK
S
S
OH
diastereomers
g. Epoxides with LiAlH4 (LAH) (followed by workup = neutralization).
1. LiAlH4
O
2. WK
achiral
HO
HO
O
chiral
1. LiAlH4
2. WK
R
O
No inversion,
but priorities
have changed.
S
1. LiAlH4
OH
achiral
2. WK
R
1. LiAlH4
No inversion,
but priorities
have changed.
OH
achiral
O
2. WK
S
S
S
R
OH
not stereoismers
h. Epoxides with NaBH4 (followed by workup = neutralization).
O
1. NaBH4
2. WK
O
R
achiral
HO
HO
chiral
1. NaBH4
2. WK
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
S
No inversion,
but priorities
have changed.
Synthetic possibilities
Chem 315
O
Beauchamp
1. NaBH4
34
OH
achiral
2. WK
No inversion,
but priorities
have changed.
R
1. NaBH4
O
OH
achiral
2. WK
S
S
S
R
not stereoismers
OH
i. Epoxides with cuprates (followed by workup = neutralization).
1. (CH3)2Cu Li
cuprate reagent
2. WK
O
achiral
HO
CH3
HO
O
1. (CH3)2Cu Li
cuprate reagent
2. WK
R
O
CH3
1. (CH3)2Cu Li
cuprate reagent
2. WK
OH
achiral
CH3
not stereoismers
R
O
S
achiral
S
R
OH
S
R
CH3
enantiomers
S
OH
achiral
CH3
S
1. (CH3)2Cu Li
cuprate reagent
2. WK
S
OH
S
j. Epoxides with lithium diisopropyl amide (LDA, followed by workup = neutralization).
Li
1.
R
R
R
O
lithium diisopropylamide (LDA)
2. WK
S
Li
1.
O
OH
R
N
N
R
R
lithium diisopropylamide (LDA)
2. WK
R
Li
1.
OH
N
O
R
R
achiral
lithium diisopropylamide (LDA)
2. WK
R
O
S
S
not stereoismers
Li
1.
R
N
R
R
lithium diisopropylamide (LDA)
2. WK
S
S
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
S
OH
OH
Synthetic possibilities
Chem 315
Beauchamp
35
k. Epoxides with Grignard reagents (followed by workup = neutralization).
H2
C
1.
H3C
O
H2C
(MgBr)
achiral
HO
Grignard reagent
2. WK
H2
C
1.
O
HO
H3C
H2C
(MgBr)
chiral
Grignard reagent
R
R
2. WK
H2
C
1.
O
H3C
H2C
OH
(MgBr)
achiral
Grignard reagent
2. WK
S
R
H2
C
1.
O
H3C
H2C
(MgBr)
S
R OH
S OH
Grignard reagent
S
S
2. WK
not stereoismers
R
S
l. Epoxides with organolithium reagents (followed by workup = neutralization).
1. H3C
O
organolithium reagent
HO
HC
H3C
1. H3C
O
1. H3C
O
S
S
chiral
R
organolithium reagent
H3C
1. H3C
Li
2. WK
HC
R
HO
organolithium reagent
H3C
O
achiral
2. WK
HC
R
Li
OH
Li
achiral
2. WK
R
organolithium reagent
HC
H3C
R OH
Li
2. WK
S OH
not stereoismers
S
S
S
m. Epoxides with conjugate base of phthalimide (followed by hydrolysis and workup = neutralization).
1.
O
NaOH
N
H
HO
O
2. epoxide
3. NaOH
4. WK
O
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
NH2
achiral
Synthetic possibilities
Chem 315
Beauchamp
O
1.
NaOH
N
O
2. epoxide
3. NaOH
4. WK
R
HO
H
NH2
NaOH
N
H
O
2. epoxide
3. NaOH
4. WK
OH
O
R
NaOH
N
2. epoxide
3. NaOH
4. WK
S
achiral
NH2
O
1.
O
S
chiral
R
O
O
1.
R
36
NH2
R OH
H
O
S OH
not stereoismers
S
S NH2
S
6. a. Aldehydes and ketones in aqueous acid form carbonyl hydrates.
O
H2SO4 / H2O
(H3O+)
H
HO
carbonyl hydrate
O
H2SO4 / H2O
(H3O+)
OH
H
HO
OH
carbonyl hydrate
OH
O
H2SO4 / H2O
(H3O+)
OH
carbonyl hydrate
O
OH
H2SO4 / H2O
(H3O+)
OH
carbonyl hydrate
b. Aldehydes and ketones in aqueous base form carbonyl hydrates.
O
NaOH
H 2O
H
O
HO
carbonyl hydrate
NaOH
H 2O
carbonyl hydrate
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
OH
H
HO
OH
Synthetic possibilities
Chem 315
Beauchamp
37
OH
O
NaOH
H 2O
OH
carbonyl hydrate
OH
O
NaOH
H 2O
OH
carbonyl hydrate
c. Aldehydes and ketones with Jones reagent. Converts aldehydes to carboxylic acids.
O
CrO3
acid / water
Jones
H
OH
O
CrO3
acid / water
Jones
d. Aldehydes and ketones with Zn/HCl (Clemmenson reduction).
O
Zn / HCl
Clemmenson reduction
H
O
Zn / HCl
Clemmenson reduction
O
Zn / HCl
Clemmenson reduction
O
Zn / HCl
Clemmenson reduction
e. Aldehydes and ketones with hydrazine and base (Wolff-Kishner reduction).
O
H2NNH2 / RO / ∆
H
O
O
Wolff-Kishner reduction
H2NNH2 / RO / ∆
Wolff-Kishner reduction
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
No reaction with ketones.
Synthetic possibilities
Chem 315
Beauchamp
38
O
H2NNH2 / RO / ∆
Wolff-Kishner reduction
O
H2NNH2 / RO / ∆
Wolff-Kishner reduction
f. Aldehydes and ketones with LiAlH4 (LAH).
1. LiAlH4
O
2. WK
achiral
OH
H
OH
O
1. LiAlH4
2. WK
enantiomers (R and S)
OH
O
OH
1. LiAlH4
2. WK
achiral diastereomers
OH
O
1. LiAlH4
OH
R
S
2. WK
chiral enantiomers
g. Aldehydes and ketones with NaBH4.
O
1. NaBH4
2. WK
OH
H
achiral
OH
O
1. NaBH4
2. WK
enantiomers (R and S)
OH
O
OH
1. NaBH4
2. WK
achiral diastereomers
OH
O
1. NaBH4
R
2. WK
chiral enantiomers
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
OH
S
Synthetic possibilities
Chem 315
Beauchamp
39
h. Aldehydes and ketones with cyanide, cyanohydrin synthesis or conjugate addition to alpha-beta
unsaturated C=O.
OH
cyanohydrins
O
1. NaCN
2. acid addition
C
H
enantiomers (R and S)
cyanohydrins
O
N
N
HO
C
1. NaCN
2. acid addition
enantiomers (R and S)
cyanohydrins
OH
O
N
C
1. NaCN
2. acid addition
achiral diastereomers
O
O
conjugate addition,
R and S enantiomers
1. NaCN
2. acid addition
C
N
i. Aldehydes and ketones with terminal acetylides.
OH
Na
O
1. R
2. WK
H
enantiomers (R and S)
O
Na
enantiomers (R and S)
1. R
2. WK
O
R
R
HO
OH
Na
R
1. R
2. WK
achiral diastereomers
O
Na
1. R
2. WK
OH
R
enantiomers (R and S)
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
Synthetic possibilities
Chem 315
Beauchamp
40
j. Aldehydes and ketones with LDA makes enolates (carbanion nucleophiles).
O
R
O
enolate
Li
N
R
H
lithium diisopropylamide (LDA)
H
O
enolate
Li
N
R
O
R
lithium diisopropylamide (LDA)
enolate
O
N
R
O
Li
R
lithium diisopropylamide (LDA)
O
N
R
Li
O
enolate
R
lithium diisopropylamide (LDA)
k. Aldehydes and ketones with Grignard (Mg) reagents.
OH
H2
C
1.
O
H3C
H2C
(MgBr)
Grignard reagent
2. WK
H
O
enantiomers (R & S)
OH
H2
C
1.
H3C
H2C
(MgBr)
Grignard reagent
2. WK
enantiomers (R & S)
O
OH
H2
C
1.
H3C
H2C
(MgBr)
Grignard reagent
2. WK
diastereomers (cis & trans)
O
OH
H2
C
1.
H3C
H2C
(MgBr)
Grignard reagent
2. WK
enantiomers (R & S)
l. Aldehydes and ketones with organolithium reagents.
OH
1. H3C
O
HC
H
Li
organolithium
reagent
H3C
2. WK
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enantiomers (R & S)
Synthetic possibilities
Chem 315
Beauchamp
OH
1. H3C
O
41
HC
Li
organolithium
reagent
H3C
enantiomers (R & S)
2. WK
O
1. H3C
OH
HC
Li
organolithium
reagent
H3C
diastereomers (cis & trans)
2. WK
O
1. H3C
OH
HC
Li
organolithium
reagent
H3C
2. WK
enantiomers (R & S)
m. Aldehydes and ketones with cuprates.
O
H
O
O
1. (CH3)2Cu Li
cuprate
reagent
2. WK
Cuprates react slowly with
ketones, esters and aldehydes.
1. (CH3)2Cu Li
cuprate
reagent
2. WK
Cuprates react slowly with
ketones, esters and aldehydes.
1. (CH3)2Cu Li
cuprate
reagent
2. WK
Cuprates react slowly with
ketones, esters and aldehydes.
O
O
1. (CH3)2Cu Li
cuprate
reagent
2. WK
conjugate addition
to α,β-unsaturated
carbonyl compounds
CH3
n. Aldehydes and ketones with secondary amines (enamine synthesis, alkylation, hydrolysis).
H
O
N
TsOH (-H2O)
N
E & Z possible
2o amines
H
H
H
O
N
TsOH (-H2O)
N
o
2 amines
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
E & Z possible
Synthetic possibilities
Chem 315
Beauchamp
42
H
O
N
TsOH (-H2O)
N
2o amines
achiral
R also possible
S
H
O
N
TsOH (-H2O)
N
2o amines
o. Aldehydes and ketones with primary amines (imine synthesis).
O
N
NH2
TsOH (-H2O)
H
E & Z possible
H
O
N
NH2
TsOH (-H2O)
E & Z possible
O
N
NH2
TsOH (-H2O)
E & Z possible
O
N
NH2
TsOH (-H2O)
E & Z possible
p. Aldehydes and ketones with ammonia + NaBH3CN = primary amine synthesis.
O
H
1. NH3
2. NaH3BCN
3. WK
NH2
1. NH3
2. NaH3BCN
3. WK
NH2
O
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
Synthetic possibilities
Chem 315
Beauchamp
43
q. Aldehydes and ketones primary amine + NaBH3CN = secondary amine synthesis.
1.
O
NH2
HN
NH2
HN
2. NaH3BCN
3. WK
H
O
1.
2. NaH3BCN
3. WK
r. Aldehydes and ketones secondary amine + NaBH3CN = tertiary amine synthesis.
1.
O
N
NH
H
2. NaH3BCN
3. WK
1.
O
N
NH
2. NaH3BCN
3. WK
s. Aldehydes and ketones ethylene glycol, acid, dehydration: ketal and acetal synthesis = protection).
O
OH
O
HO
O
TsOH (-H2O)
H
acetal =
protected aldehyde
H
O
OH
HO
O
ketal =
protected ketone
O
TsOH (-H2O)
O
O
OH
HO
O
TsOH (-H2O)
ketal =
protected ketone
O
O
OH
HO
TsOH (-H2O)
O
ketal =
protected ketone
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
Synthetic possibilities
Chem 315
Beauchamp
44
t. Aldehydes and ketones with 1. LDA 2. RX = alkylation of C=O.
O
O
1.
Li
N
R
H
R
lithium diisopropylamide (LDA)
2. RX (R = Me, 1o, 2o)
H
O
1.
Li
N
R
achiral
R
O
R
lithium diisopropylamide (LDA)
2. RX (R = Me, 1o, 2o)
O
1.
achiral
enantiomers and diastereomers
(RR, SS, RS, SR)
Li
N
R
R
O
R
lithium diisopropylamide (LDA)
2. RX (R = Me, 1o, 2o)
R
O
R
1.
Li
N
O
R
R
lithium diisopropylamide (LDA)
2. RX (R = Me, 1o, 2o)
enantiomers (R and S)
u. Aldehydes and ketones with 1. LDA 2. epoxide = alkylation of C=O.
O
1.
Li
N
O
R
H
R
lithium diisopropylamide (LDA)
O
2. epoxide
H
OH
S
S
O
1.
Li
N
O
R
R
H
lithium diisopropylamide (LDA)
O
OH
2. epoxide
S
1.
N
O
R
Li
R
lithium diisopropylamide (LDA)
O
O
OH
2. epoxide
S
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
Synthetic possibilities
Chem 315
Beauchamp
45
v. Aldehydes and ketones with 1. LDA 2. another C=O = addition to C=O. Forms a beta hydroxyl
carbonyl, which can be dehydrated in acid or base (with heat) to an α,β-unsaturated carbonyl
compound.
O
Li
1.
O
N
O
R
R
lithium diisopropylamide (LDA)
H
H
O
acid
2. carbonyl
H
(-H2O)
OH
O
Li
1.
O
N
O
R
R
lithium diisopropylamide (LDA)
O
acid
2. carbonyl
(-H2O)
OH
Li
1.
N
O
R
O
lithium diisopropylamide (LDA)
O
acid
R
(-H2O)
O
2. carbonyl
OH
w. Aldehydes and ketones with mCPBA (Baeyer-Villigar oxidation) to form esters (cyclic = lactones).
O
O
H
O
H
O
aldehyde forms
carboxylic acid
O
meta chloroperbenzoic acid
(mCPBA)
OH
O
O
O
H
O
O
O
meta chloroperbenzoic acid
(mCPBA)
The better R+ group
migrates better.
O
O
O
H
O
O
meta chloroperbenzoic acid
(mCPBA)
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc
O
Cyclic esters
are called
lactones.
Synthetic possibilities
Chem 315
Beauchamp
46
7. Show the products of the following miscellaneous reactions.
O
1. NaOH
2. RX (R = methyl, 1o, 2o)
O
R
OH
O
O
O
SOCl2
OH
Cl
O
O
R
OH
R
Cl
O
O
O
NH3
NH2
Cl
O
N
SOCl2
C
NH2
O
O
R
NH2
R
N
H
Cl
O
O
R
R
R
NH
N
Cl
R
Z:\classes\316\Organic reactions overview\final exam option - rxn examples w answers.doc