homework 5 organic chemistry mcat review summer 2012 brent iverson
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Homework 5Organic Chemistry MCAT ReviewSummer 2012Brent Iverson
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1. For the following reactions, draw the predominant product or products. When a new chiral center is created, mark it with an asterisk (*) and if a racemic mixture is produced, you must write "racemic" under your structure. If an E,Z mixture is produced as the result of a dehydration step, write E,Z mixture, but you only have to draw one isomer, not both. These directions are different than you may have seen before, and are intended to make it easier for you. You should read them again so you know what we want.
H
OH O
O
H
O
H
H
O
1.0 eq. NaOH
1) catalytic NaOH2) H3O / Δ
(No acid or heat)
E,Z Mixture
*
*
Racemic
No dehydration here because no acid/heat treatment
1) 0.5 eq. LDA
2) H3O / Δ
E,Z Mixture
ON
H / H N
O O
*Racemic
O
*Racemic
1)Br
2) H3O
1) Cl2) H3O
O
3
Br
Br
HBr
O
O
O
O
HBr
Br
O
O
O
O O
O
O O
2. For the following reactions, draw the predominant product or products. When a new chiral center is created, mark it with an asterisk (*) and if a racemic mixture is produced, you must write "racemic" under your structure. If an E,Z mixture is produced as the result of a dehydration step, write E,Z mixture, but you only have to draw one isomer, not both. These directions are different than you may have seen before, and are intended to make it easier for you. You should read them again so you know what we want.
Racemic1) 1.0 eq. LDA
1) 0.5 eq. NaOEt
2) H3O (Mild acid)
*
2)
3) H3O(Mild acid)
no heat
Racemic
*
1.0 eq. LDA
no heat
Racemic
(Hot; thermodynamic control)
(Cold; kinetic control)
1,4 addition
1,2 addition
1.0 eq. NaOHO
O
HO
H2CrO4
excess
cat. H2SO4
excess OH
OHHO
O O
OO
OO
4
OH
OH
O
H2CrO4
H
O
OH
H
O
HOOH
MgBr
H
OO
OH
H
Ph3P CHCH3
H
*
racemic
*
cat. NaOH
1)
2) mild H3O
cat. H
1) NaBH42) H2O
*
racemic
3. Fill in the boxes with the predominant product formed under the reaction conditions. If a new chiral center is formed in a racemic mixture, put an asterisk (*) next to it and write "racemic". If there is an aldol reaction on this page DO NOT DEHYDRATE IT!!!
Z product
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O
O
O
O O
O
O O
Br
OH
O
O
O O
MgBr
HO
0.5 eq. NaOEt
1) Strong H3O
2) Heat (Δ)
+ CO2
Mild H3O
No heat
1)
2) H3O
*
*
Racemic
Racemic
4. Fill in the boxes with the predominant product formed under the reaction conditions. If a new chiral center is formed in a racemic mixture, put an asterisk (*) next to it and write "racemic".
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CN
H3O
O
OH
CuLi
SOCl2
O
Cl
O O
NH
OO
O
O
MgBr
OH
OH
O
N
N
5. Fill in the box with the product or products that are missing from the following chemical reaction equations. When a racemic mixture is formed, you must write "racemic" under both structures EVEN THOUGH YOU DREW BOTH STRUCTURES.
heat
1) LiAlH4
2) H2O
21)
2) H2O
1)2) HCl / H2O
Racemic
2 eq.
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OH
O
CH2-P(Ph)3
CH3
CH2
SOCl2
Cl
O
1. (CH3)2CuLi
OH
O
O
NH3
NH2
O
OH
OHOH
CH3
O
6. Fill in the box with the product or products that are missing from the following chemical reaction equations. When a racemic mixture is formed, you must write "racemic" under both structures EVEN THOUGH YOU DREW BOTH STRUCTURES.
1) NaOH / excessBr22) H3O + CHBr3
Haloform reaction
H2 / Pd
1) LiAlH4
2) H2O
(1st semester)
CH3Cu + LiCl
Note: in principle, this could react on either side of the carbonyl, but due to accessibility, i.e. the methyl group is more accessible, reaction is always observed at the methyl group in these reactions.
2. H2O
heat
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7. For the following reactions, draw the predominant product or products. When a new chiral center is created, mark it with an asterisk (*) and if a racemic mixture is produced, you must write "racemic" under your structure. If an E,Z mixture is produced as the result of a dehydration step, write "E,Z mixture", but you only have to draw one isomer, not both. These directions are different than you may have seen before, and are intended to make it easier for you. You should read them again so you know what we want.
1) 1.0 eq.NaOEt
2) H3O (mild acid, no heat)
O1) 1.0 eq.NaOEt
2)
3) H3O (stronger acid, with heat)
O
O
CH3
O
O
*
(racemic)
O O
O O
O
O
O
*
1) excess LiAlH4
2) H2 O
HO OH
OH2
(racemic)1) excess LiAlH4
2) H2 O
(racemic)
OH
OH
CH3*
*
*
Hardest problem: How many different stereoisomers are created in this reaction?
6(There are two meso compounds)
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O
O
Cl
O
OH
I
H2O
Br
KI
N2
CuCN
CO2H
KCN
CN
Br2
HClNaNO2
H3PO2
H2CrO4
NH2
AlCl3
H2SO4
Cl
HNO3
NiH2
Br 2FeB
r 3
NO2
Br
8. Fill in the boxes with the predominant product formed under the reaction conditions. If a new chiral center is formed in a racemic mixture, put an asterisk (*) next to it and write "racemic". If ortho/para products are created, you must draw both.
*
racemic
hν
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NH2
CuClHCl
H2
N2
Ni
Cl
KCN
H2O
Cl
O
NO2
CuCN
O
O
OH
CN
HNO3
H2SO4
CO2H
Br2FeBr3
OCH3
Br
HNO3H2SO4
MgBr
OCH3
NO2
OCH3
O2N
9. For the following reactions, fill in theboxes with the predominant product or products. When ortho/para products are both produced, you must draw both. When a new chiral center is produced, put an asterisk (*) next to it. If a racemic mixture is produced, you must write racemic.
NaNO2 / HCl
Mg ° / ether(yes, this works)
1) CO2
2) H3O(mild)
(strongwith heat)
1) 1.0 Eq. LDA
2) CH3Br
H3O
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10. For the following reactions, fill in theboxes with the predominant product or products. When ortho/para products are both produced, you must draw both. When a new chiral center is produced, put an asterisk (*) next to it. If a racemic mixture is produced, you must write racemic.
CH3
CH3
SO3H
O
Br2
FeBr3
OH
CH3
NO2
SO3HO2N
O
Br
CO2H
CO2H
CH2Br
CH3
O2N
HNO3 / H2SO4
Br2 / hν
HNO3 / H2SO4
H2CrO4
H2CrO4
*
racemic
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NO2
CH3
NO2
OH
O
O
Cl
OCH3
NO2
CH3
Br
NO2
OH
Br
Cl
OCH3
Br
O
OBr
O
O
Br
NO2
CH3
Br
NO2
OH
Br
Cl
OCH3
Br
Br2 / FeBr3
Br2 / FeBr3
Br2 / FeBr3
Assume only one Br atom adds
Br2 / FeBr3
11. For the following reactions, fill in theboxes with the predominant product or products. When ortho/para products are both produced, you must draw both. When a new chiral center is produced, put an asterisk (*) next to it. If a racemic mixture is produced, you must write racemic.