CHEM 210
[CHAPTER 5: STEREOCHEMISTRY – STEREOISOMERS
Skills you must master for Chapter 5:
1. Know the difference between isomeric types
2. Be able to draw all possible stereoisomers for a compound and indicate the interrelationships.
3. Learn how to apply these skills to cyclic compounds
Isomerism:
Problem 1: Determine whether the following molecules are identical, constitutional isomers, enantiomers or
diastereomers.
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
l.
m.
m.
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CHEM 210
[CHAPTER 5: STEREOCHEMISTRY – STEREOISOMERS
Problem 1: Continued.
n.
o.
p.
q.
r.
s.
t.
u.
v.
w.
x.
y.
z.
aa.
bb.
cc.
dd.
ee.
ff.
gg.
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CHEM 210
[CHAPTER 5: STEREOCHEMISTRY – STEREOISOMERS
Problem 2: Draw all stereoisomers for the following molecules; indicate the stereochemical interrelationships for all
possible pairs.
Problem 3: Menthol is a member of the terpene family of natural products. It exists in a (1R,2S,5R) form and a (1S,2R,5S)
form. Draw the two molecules in their most stable chair conformer(s). Are these two compounds enantiomers or
diastereomers ?
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Fall 2011
CHEM 210
[CHAPTER 5: STEREOCHEMISTRY – STEREOISOMERS
KEY
Problem 1:
a.
diastereomers
b.
enantiomers
c.
enantiomers
d.
diasteromers
e.
diastereomers
f.
diastereomers
g.
diastereomers
h.
Identical - (3R,4S)-3,4-dimethylhexane
i.
Constitutional isomers
j.
Constitutional isomers
k.
diastereomers
l.
identical
m.
enantiomers
m.
diastereomers
n.
identical
o.
identical
p.
identical
q.
identical
r.
enantiiomers
s.
identical
t.
enatiomers
u.
diastereomers
v.
enantiomers
w.
diastereomers
x.
enantiomers
y.
enantiomers
z.
identical
aa.
diastereomers
bb.
constitutional isomers
cc.
diastereomers
dd.
enantiomers
ee.
Constitutional isomers
ff.
diastereomers
gg.
diastereomers
Problem 2:
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CHEM 210
Problem 3:
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Fall 2011
[CHAPTER 5: STEREOCHEMISTRY – STEREOISOMERS
CHEM 210
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Fall 2011
[CHAPTER 5: STEREOCHEMISTRY – STEREOISOMERS