Problems 399
- Only one bromoether (ignoring stereoisomers) is obtained from the reaction of the following alkyl dihalide with methanol:
Give the structure of the ether.
- Starting with cyclohexane, how could the following compounds be prepared?
a. cyclohexyl bromide b. methoxycyclohexane c. cyclohexanol
- For each of the following reactions, give the substitution products, assuming that all the reactions are carried out under
conditions; if the products can exist as stereoisomers, show what stereoisomers are formed:
a. c.
b. d.
- Explain why tetrahydrofuran can solvate a positively charged species better than diethyl ether can.
- Propose a mechanism for each of the following reactions:
a. b.
- Which of the following will react faster in an reaction?
- Alkyl halides have been used as insecticides since the discovery of DDT in 1939. DDT was the first compound to be found that
had a high toxicity to insects and a relatively low toxicity to mammals. In 1972, DDT was banned in the United States because it is
a long-lasting compound and its widespread use caused accumulation in substantial concentrations in wildlife. Chlordane is an
alkyl halide insecticide that is used to protect wooden buildings from termites. Chlordane can be synthesized from two reactants in
a one-step reaction. One of the reactants is hexachlorocyclopentadiene. What is the other reactant? (Hint:See Section 8.9.)
- Explain why the following alkyl halide does not undergo a substitution reaction, regardless of the conditions under which the
reaction is run:
Cl
Cl
Cl
Cl
Cl
H
Cl
Cl
Cl
Cl
Chlordane
(CH 3 ) 3 C
or
H (CH 3 ) 3 C
H Br H H
Br
SN 1
H 2 O
OH
H
CH 3
H
CH 3
CH 3
OH
CH 3
+
H 3 C CHCH 3
Br
H 2 O
CH Br
CH 3 OH
CH 3
tetrahydrofuran
O
diethyl ether
CH 3 CH 2 OCH 2 CH 3
(3S,4R)-3-bromo-4-methylhexane+CH 3 O- (3R,4S)-3-bromo-4-methylhexane+CH 3 O-
(3S,4S)-3-bromo-4-methylhexane+CH 3 O- (3R,4R)-3-bromo-4-methylhexane+CH 3 O-
SN 2
Br
Br
AU: OK as changed?
