Chem 212
Survey of Organic and Biochemistry
Fall 2006
_____________________________
Print your full name legibly in the space above.
Exam 2: Ch. 6-11
7 November 2006
(Don’t forget to vote, it’s multiple choice and there are no wrong answers!)
Instructions:
1. If you leave the room for any reason you may not return to continue the exam.
2. No books, notes, or calculator of any kind are permitted (including cell phones.) You may borrow a model kit.
3. Put all your answers on this exam paper. If you want something graded which is written on scratch paper, you must
indicate so in the regular space for the answer.
Good Luck!
1. (5 pts) Mark each stereocenter in the following molecules with an asterisk (*)
OH
O
OH
HO
SH
Br
Br
Br
OH
HO
HO
OH
2. (6 pts) Assign priorities to the groups in each set:
a. –C(CH3)3
–CH2Br
–CHO (aldehyde)
–CH2CH(CH3)2
b.
–C6H5 (phenyl)
–C≡CH
-CH2OH
–Br
c.
–NH2
–CH2CCl3
–CH2CH2CBr3
–OH
3. (5 pts) For each of the following tetrahedral centers with priorities shown, assign the
chirality designation as either R or S:
3
1
3
2
4
1
3
2
4
3
4
1
2
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2
3
1
4
4
1
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Chem 212
Survey of Organic and Biochemistry
Fall 2006
4. (5 pts) Assign the chirality (R or S) for each of the chiral centers in the following
molecules.
H3C
CH2
NH2
S
CH3
OH
N
O
O
CH3
CH3
O
O
HO
5. (6 pts) Write the products of the acid-base reactions for each of the following, then circle
the side favored at equilibrium and calculate the equilibrium constant (may be written as
10x.x). Refer to the table provided for pKa values.
a. CH3COOLi + C6H5OH
b. KOH + HC≡CH 
c. CH3OH + HNO3 
6. (3 pts) Write the appropriate formula or structure for:
a. The conjugate acid of Na2CO3
b. The conjugate base of CH4
c. The conjugate acid of HSO4-
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Chem 212
Survey of Organic and Biochemistry
Fall 2006
7. (6 pts) The following graph is a titration curve for 2-aminopropanoic acid. Based on this
information, draw the structures of 2-aminopropanoic acid that would predominate at
each of the three different pH values given below.
14
13
12
11
10
9
pH
8
7
6
5
4
3
2
1
0
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
NaOH (mL)
pH = 2.0
pH=7
pH=12.5
8. (6 pts) Classify each of the following amines using all terms that apply from among the
following list: primary, secondary, tertiary, quaternary, aliphatic, aromatic, heterocyclic.
H3C
N
CH3
NH2
NH
CH3
+
NH
H3C
N
CH3
NH2
9. (6 pts) In certain bacterial infections, (CH3)3NH+ Cl- is produced. A clinical test for the
presence of this substance (and confirmation of the bacterial infection) is performed by
adding a drop of sodium hydroxide solution to a sample, and smelling the resultant
mixture. Explain the chemistry behind this test using words and a chemical reaction.
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Chem 212
Survey of Organic and Biochemistry
Fall 2006
10. (14 pts) Give the products of the following reactions:
CH3
OH
O
CH3
HCl (one equiv.)
N
N
CH3
CH3
O
OH
O
H
H2, Pt (excess)
+
O
O
+
N
NaBH 4
H , H2O
H
O
+
H , H2O
O
H3C
+
O H2, Pt (two equiv.)
O
CH3
NH2
CH3
H3C
OH
H
+
OH
O
O
O
OH
O
1) SOCl 2
2)
O
O
P
LiAlH 4
OH
NH2
hydrolysis
O
CH3
OH
HO
OH
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CrO 3, Pyridine
Chem 212
Survey of Organic and Biochemistry
11. (10 pts) Give the products of the following reactions:
O
CH 3OH, H
+
OH
+
NaHCO 3
H3N
N
O
H3C
(enol formation)
H3C
O
+
Ag (Tollen's reagent)
HO
O
OH
Polymerize
+
HO
(H catalyst)
12. (6 pts) Draw the structure of each of the following substances:
a.
N,N-Dimethyl-3-aminooctanoic acid
d. An example of a -lactone
b.
2,4-pentanedione
e. Cyclohexyl pentanoate
c.
Ethanedioic acid
f. Potassium decanoate
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Fall 2006
Chem 212
Survey of Organic and Biochemistry
Fall 2006
13. (4 pts) Draw the structure of a substance that has the formula C6H12O which gives a
negative Tollen’s test and a positive iodoform test.
14. (4 pts) Suppose the following molecule is a possible new drug, and a biochemist
hypothesizes that the drug would be more potent if the carboxylic acid group could be
made more acidic. What changes could be made to meet this requirement?
CH3
OH
HO
O
N
15. (4 pts) Would you expect the molecule shown below to form a micelle? You must
explain your answer for credit.
O
O
CH3
+
S
N
-
O H3C
CH3
16. (5 pts) The structure on the left is acetylcholine, an important neurotransmitter (nerve cell
signaling molecule.) The activity of acetylcholine is stopped when the ester bond is
hydrolyzed. At right is an analog of acetylcholine; its structure is very similar to
acetylcholine. What do you expect to be different about the analog compared with
acetylcholine? How might this be useful as a drug or tool in the biology laboratory?
CH3
H3C
H3C
O
CH3
+
H3C
N
O
Acetylcholine
CH3
O
+
N
H3C
NH
Acetylcholine analog
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CH3
Chem 212
Survey of Organic and Biochemistry
Fall 2006
17. (5 pts) The following table from Chemical & Engineering News shows the top 10 best
selling drugs of 2003 and indicates the form of the active ingredient(s). Based on this
information, which brand or brands of these drugs are candidates for the chiral switch
strategy discussed in class? What benefit is there to the pharmaceutical company to do a
chiral switch? Explain your answer.
Acid
HI
H2SO4
HBr
HCl
(CH3)2OH+
CH3OH2+
H 3O +
HNO3
H3PO4
HF
HCOOH
CH3CH(OH)COOH
CH3COOH
H2CO3
H2PO4H3BO3
NH4+
HCN
C6H5OH
HCO3HPO42H 2O
(CH3)3COH
HCCH
NH3
CH3CH3
pKa
-10
-9
-9
-7
-2.9
-2.5
-1.74
-1.4
2.12
3.2
3.75
3.86
4.75
6.37
7.21
9.14
9.25
9.31
9.89
10.25
12.66
15.7
18
25
38
50
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