CHEMISTRY 3331: Fundamentals of Organic Chemistry I
Second Exam
Prof. Randolph P. Thummel
Prof. Ognjen Š. Miljanić
Name: _______________________________________
(print legibly) Last
First
March 27, 2009
Last 4 Digits of Student ID Number: _______________
Read all directions very carefully. Write your answer legibly in the designated spaces and think about
what you are doing. Give only one answer for each question. Total number of points is 100.
1. (8 points) Honey is an approximately 1 : 1 mixture of sugars known as glucose and fructose. The
Fischer projection formulas for these two sugars are shown below. Assign an (R)- or an (S)configuration to each of the chiral carbons in these two molecules.
CHO
H
HO
CH2OH
OH
O
H
HO
H
H
OH
H
OH
H
OH
H
OH
CH2OH
CH2OH
f ructose
glucose
Glucose and fructose are (circle one):
isomers
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FINAL SCORE
enantiomers
diastereomers
1
same compound
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2. (16 points) In the provided boxes, draw the structures that correspond to the following IUPAC names:
(a) trans-5,6-dimethyl-1,3-cyclohexadiene
(b) 1,1-divinylcyclobutane
(c) (E)-2,4-dibromo-3-methyl-2-hexene
(d) 4,4-dichloro-1-methylcyclopentene 2
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3. (20 points) For each of the reactions or series of reactions below, draw the structure of the FINAL
major organic product in the box provided.
H3C
CH3
Br
t-BuOK
t-BuOH
3
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4. (20 points) Consider the reaction shown below and propose a detailed step-by-step mechanism to
explain the formation of the two alkene products. Show each intermediate, all charges, and use curved
arrows to indicate the flow of electrons. Do NOT draw transition states (dotted bonds). A third
product with the formula C9H18O is also formed; draw its structure in the box.
4
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5. (20 points) Propose a synthetic route that will achieve the following transformation. NOTE: You will
need to use more than one step in your sequence! Do not show mechanisms.
5
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6. (20 points) Compound A shown below has two chiral centers. Draw a Fischer projection of
compound A and assign an (R)- or an (S)-configuration to each of the two chiral centers. When
exposed to (CH3)3O−K+, compound A gives an alkene B; when exposed to K+I−, compound A
produces compound C. In the provided boxes, draw compounds B and C and clearly indicate their
stereochemistry. Assign an (E)- or a (Z)-configuration to the double bond in alkene B. Assign an (R)or an (S)-configuration to each of the chiral centers in C. CH3
CH2CH3
Br
H3C
H
H
H
H
(CH3)3CO-K+
K+I-
Label chiral carbons as (R)- or (S)-
Is this alkene (E)- or (Z)-?
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