Final Exam
Comprehensive Exam
Chem 240
Final Exam
Name___________________
December 18, 2000
CLOSED BOOK EXAM - No books or notes allowed. All work must be shown for full
credit. You may use a calculator.
Question
1(18 )
Credit
Question
7(24)
2(10)
8(36)
3(20)
9(12)
4(12)
10(8)
5(16)
11(15)
6(9)
12(20)
TOTAL
TOTAL
Credit
I want my final to count for 300 pts. ______________________________
(This will drop your lowest exam)
Signature
1) Please name or draw the structure of the following compounds.
Br
H
CH2OH
Cl
I
OH
Cl
H3C
H2C
CH 3
H
CH CH
H2C
H2C
CH2
Cl
CH 3
CH 3
HO
H
C 2H5
H3C
Br
O
C
C
CH 3
C
C
2) Please draw the most stable form of trans-1,3-dimethyl cyclohexane.
3) Please draw the complete mechanism of the acid catalyzed addition of ethanol to 3methyl butene and then draw the reaction diagram.
4) Please draw the product of the Saytzeff elimination of HBr from the following
compound. Two products are possible, but only one is made. Show how both could be
made and EXPLAIN which one is possible and why.
5) Circle the type of reaction occuring in each of the following reactions. If more than
one reaction type occurs label the major and minor product.
HI
H
Et h er
SN1
SN2
E1
E2
SN1
SN2
E1
E2
SN1
SN2
E1
E2
SN1
SN2
E1
E2
OH
O
C C C C
H 2 SO 4
CH 3 O H
C
H
Et O H , Hea t
Cl
Cl
C C C C
I s o PrO I s o PrO H
6) There are three forces that hold liquids together. Please explain how each of these
contributes to the overall bonding in liquids and order them according to relative strength.
7) Label each of the following compounds R,S.
CH3
Cl
H
CH3 C Cl
H C Cl
H C CH3
Cl C CH 3
H
A
Cl C H
CH 3
B
CH 3
C H
H
CH3
H C Cl
Cl C
Cl
CH 3
C
D
7b) Which are enantiomers and diasteromers, and which compound (if any) is meso?
8) Please give the product for each of the following reactions.
C
BH 3 , H 2 O 2
C C
H2O, K OH
H Cl
Per o x id e
CH 3
Cl
EtO H , Hea t
C C C C
C
CH 3
H 2 SO 4 , H 2 O
K MnO 4
H2O, KOH
CH 3
PBA
Cl
C C C
KI
C
Cl
C C C C
1) Mg
2) H 2 O
OH
P / I2
Os O 4
H2O2, H2O
C
C
C C
C
C C OH
Hg ( O Ac) 2
CH 3 O H , NaBH 4
H 2 SO 4 , Hea t
9a) Please show all the steps in the free radical chlorination of 2 methyl butane. It is
important for the chlorine to become attached to the proper carbon so be careful of which
carbon you choose to halogenate.
9b) Please give the ratio of products made in the free radical chlorination of 1,1 dimethyl
cyclohexane.
10) Please draw the Lewis structure of C4H4O4
11) Please give all the steps in the Fisher ester synthesis of ethyl acetate.
12) Starting with alkanes of two carbons or less synthesize any two of the following;
Br
O
C
C
C
C
C
C
C
C
OH
CH3
H3C
O
C
CH3
CH3
O
O
C
C
C
O
CH3
Chem 240
Final Exam
Name__Answer Key ______
December 18, 2000
CLOSED BOOK EXAM - No books or notes allowed. All work must be shown for full
credit. You may use a calculator.
Question
1(18 )
Credit
Question
7(24)
2(10)
8(36)
3(20)
9(12)
4(12)
10(8)
5(16)
11(15)
6(9)
12(20)
TOTAL
TOTAL
Credit
I want my final to count for 300 pts. ______________________________
(This will drop your lowest exam)
Signature
1) Please name or draw the structure of the following compounds.
Br
H
CH2OH
Cl
I
OH
E 3-chloro-2-iodo-2-propene-1-ol
Cl
1R,2R,3S-4-chloro-2-bromo-cyclopentanol
H3C
H2C
CH 3
H
CH CH
H2C
H2C
Cl
CH 3
CH2
CH 3
HO
H
C 2H5
H3C
3-ethyl-4-methyl-heptane
Br
3R,4R-4-chloro-3-pentanol
O
C
C
C
C
CH 3
E,Z-3-bromo-4-methyl-2,4-hexadiene
cyclopentyl(sec-butyl) ether
2) Please draw the most stable form of trans-1,3-dimethyl cyclohexane.
CH3
H3C
3) Please draw the complete mechanism of the acid catalyzed addition of ethanol to 3H
CH3
methyl butene and then draw the reaction diagram.
CH3
C
C
C
C
C
C
C
+
H
C
CH3
C
C
H
H
C
C
+
H
C2H5OH
H
H+
C
H+ +
CH3
C
C
H
C
C
C
C
H
O
C2H5
C
CH3
C
C
H
CH3
C
C
H
C
H
C
CH3
C
C
H
C
CH3
C
C
H +O
C
C2H5
H
CH3
H
C
H
HOH5C2
C
C
C
H
O
C2H5
H
H
CH3
C
C
C
C
C
C
C
+
CH3
H
H
C
C
CH3
C
C
C
H
+
H
CH3
H
C
C
C
H
+O
C
H
C2H5
C
H
4) Please draw the product of the Saytzeff elimination of HBr from the following
compound. Two products are possible, but only one is made. Show how both could be
made and EXPLAIN which one is possible and why.
Least stable
staggered
Br
Br
H
H
Br
H3C
C
C
H
C2H5
CH 3
H
H
H
H
H3C
H
H
C2H5
H
H
H3C
H
Elimination
C2H5
Moderately stable
staggered
Less stable product
C2H5
CH 3
H
Br
C2H5
CH 3
H
H
Most stable
staggered
H
C2H5
Most stable product
CH3
C
C
C
H
O
C2H5
5) Circle the type of reaction occuring in each of the following reactions. If more than
one reaction type occurs label the major and minor product.
HI
H
Eth er
SN1
SN2
E1
E2
SN1
SN2
E1
E2
SN1
SN2
E1
E2
OH
O
C C
C
C
H 2 SO 4
CH 3 O H
C
H
EtO H , Hea t
Cl
Cl
C C
Minor
Major
I s o PrO -
C
C
I s o PrO H
SN1
SN2
E1
E2
6) There are three forces that hold liquids together. Please explain how each of these
contributes to the overall bonding in liquids and order them according to relative strength.
1. Hydrogen Bonding – it is the strongest bond. It is a sharing of H’s in compound
with OH or NH bonds.
2. Dipole-Dipole – the second strongest bond. It is the attraction between + and – in
molecules with dipoles.
3. Diserson/London Forces – the weakest of the forces. Transient dipoles are made
when molecules bump into each other, and these weak dipoles attract one another.
7) Label each of the following compounds R,S.
CH3
Cl
H
CH3 C Cl
H C Cl
H C CH3
Cl C CH 3
H
2S, 3R
A
Cl C H
CH 3
2R, 3S
B
CH 3
C H
Cl
2R, 3R
C
H
CH3
H C Cl
Cl C
CH 3
2S, 3R
D
7b) Which are enantiomers and diasteromers, and which compound (if any) is meso?
A B, and D are the same compound – these are all meso so there are no enantiomers. C
and (A,B,D) are diastereomers.
8) Please give the product for each of the following reactions.
C
H2
C C
BH 3 , H 2 O 2
C C
HO
H2O, K OH
H Cl
H
Cl
H
CH3
C
C
C
H
C
Per o x id e
CH 3
Cl
EtO H , Hea t
C
C C C C
C
CH 3
C
CH3
H 2 SO 4 , H 2 O
H
OH
K MnO 4
H2O, KOH
CH 3
OH
OH
O
PBA
CH3
Cl
C C C
KI
No Rxn
1) Mg
C C C C
C
Cl
C C C C
2) H 2 O
OH
P / I2
I
Os O 4
H2O2, H2O
OH OH
C
C
C
C
C
C
C OH
Hg ( O Ac) 2
CH 3 O H , NaBH 4
C
C C C C
OCH3
H 2 SO 4 , Hea t
C C O C
C
9a) Please show all the steps in the free radical chlorination of 2 methyl butane. It is
important for the chlorine to become attached to the proper carbon so be careful of which
carbon you choose to halogenate.
Initiation
h
Cl2
2 Cl
Propagation
C
C
C
C
C
C
C
+ Cl
C
C
C
+ HCl
H
C
C
C
C
C
C
C
+ Cl2
C
C
C
+ Cl
Cl
Termination
Cl2
2 Cl
C
C
C
C
C
C
C + Cl
C
C
C
Cl
C
C
2 C
C
C
C
C
C
C
C
C
C
C
C
C
9b) Please give the ratio of products made in the free radical chlorination of 1,1 dimethyl
cyclohexane.
CH3
X
1oo
2 100-X
=
6
10
x
35X = 600 - 6X
CH3
41X = 600
X = 14.63%
1
3.5
10) Please draw the Lewis structure of C4H4O4
O
H
O
O
C
C
C
O
H
C
H
H
11) Please give all the steps in the Fisher ester synthesis of ethyl acetate.
+
O
O
OH
OH
H
+
C
C
H
OH
C
C
C
OH
C
OH
C-C-OH
C
C
OH
H
O
C
+
+
C
H
C
H2O +
+O
+
C
O
H
O
C
C
C
OH
H
C
OH
O
C
H+ +
C
C
C
OH
O
C
C
O
C
C
O C
C
+ H+
12) Starting with alkanes of two carbons or less synthesize any two of the following;
Br
O
C
C
C
C
C
C
C
C
C
OH
CH3
H3C
O
C
CH3
CH3
O
O
C
C
O
CH3