CHEMISTRY 3331
Dr. C. Cai
Dr. R. Thummel
Third Hour Exam
April 19, 2002
Name___________________________________________
(print)
Last
First
S. S. Number_____________________________________
Please read all directions carefully. Write all answers legibly in the appropriate spaces and
THINK about what you are doing. Give only ONE answer for each question (100 pts total).
1. (16 pts) Give a complete and acceptable name for each of the following compounds. Be sure
to indicate stereochemistry where this is pertinent as well as the absolute configuration of any
chiral centers.
a)
H
b)
HO
H
c)
HO
d)
H
CH3 OH
2. (30 pts) For each of the following reactions or series of reactions, draw the structure of the
principle organic product in the empty box. Give only one structure per box. Be sure to indicate
STEREOCHEMISTRY where pertinent.
CH3
a)
b)
CH Br3
KOH/H 2O
CH3
Br2
H2O
c) CH3CH2C C-C H3
KMnO 4
H2O, N eutral
1)
(d)
CH2 C C-H
B H
2
2) H2O2, H2O
e)
KMnO 4
H 2O
Br
f)
1. NaOEt
CH3
2. H2, Pd/C
CH3
Hg(OAc)2
g)
NaBH4
H2O, THF
O
h)
C
Cl
i)
C C
MgBr
H3O+
(xs)
CH3
- H2O
Na
NH3 (liq)
H3C
j)
Br
Mg
Dry ether
H+
D2O
3. (16 pts) Starting with acetylene, cyclohexanone, any alkyl halide of three carbons or less and
any necessary reagents, outline a practical synthesis for TWO (only) of the molecules shown
below. Show each intermediate and the reagents needed for each step. DO NOT GIVE
MECHANISMS.
HC CH
R-X (Š 3C)
H O H
O
or
or
CH3 CH2
OH
CH3
CH2 CH3
4. (9 Pts) Give a detailed mechanism to explain the following conversion. Show all charges and
intermediates with the correct stereochemistry, indicate the flow of electrons using arrows,
and do not draw transition state (dotted bonds)
Br
Br2
O
OH
5. (13 pts)
(a) Give a detailed mechanism to explain the following conversion. Show all charges and
intermediates, indicate the flow of electrons using arrows, and do not draw transition state
(dotted bonds)
CH3
HBr
CH3
Br
CH3
(b) Give the structure of another addition product which might be formed in this reaction.
6. (16 pts) The two alcohols on the right can be made by reacting a Grignard reagent with an
appropriate carbonyl compound. Give two different combinations which will provide the same
product. (Chenging the halogen on the Grignard is not different).
Grignard Reagent
Carbonyl Compound
+
CH2 CH3
CH3
Grignard Reagent
Carbonyl Compound
OH
CH2 CH3
+
Grignard Reagent
Carbonyl Compound
+
OH
CH CH3
Grignard Reagent
Carbonyl Compound
+
7. (7 pts EXTRA CREDIT) Draw the structure of an alkene which would give 4,4-dimethyl-2,6heptanedione upon reductive ozonolysis.
O
O3
O
CH3-S-CH3
4,4-dimethyl-2,6-heptanedione
8. (7 pts MORE EXTRA CREDIT !!) In the box draw the structure of the epoxide which would
give trans-1,2-cyclopentanediol upon treatment with aqueous acid.
H3O+
trans-1,2-cyclopentanedioll