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CHAPTER 13 463 
 
(c) The oxygen atom is connected to two carbon atoms, 
each of which is sp3 hybridized. Therefore, each of the 
CO bonds is cleaved, giving two equivalents of 2-
bromopropane. 
 
 
 
(d) The oxygen atom is connected to two carbon atoms, 
each of which is sp3 hybridized. Therefore, each of the 
CO bonds is cleaved. As a result, the ring is opened, 
giving a dibromide, as shown. 
 
 
 
13.28. Ethers have the following structure: 
 
 
 
We are looking for ethers with the molecular formula 
C4H10O, which means that the four carbon atoms must be 
contained in the two R groups of the ether. One 
possibility is that each R group has two carbon atoms. 
 
 
 
Alternatively, one R group can have three carbon atoms 
and the other R group can have one carbon atom. The R 
group containing three carbon atoms can either be a 
propyl group or an isopropyl group, giving the following 
two additional isomers: 
 
O O
1-methoxypropane
2-methoxypropane(methyl propyl ether)
(isopropyl methyl ether) 
 
In total, there are three constitutionally isomeric ethers 
with the molecular formula C4H10O. 
 
 
13.29. 
(a) The desired transformation involves addition of H 
and OEt across a  bond. This can be achieved via 
alkoxymercuration-demercuration, where EtOH is used 
as the alcohol during the alkoxymercuration step: 
 
 
 
Alternatively, cyclohexene can be treated with dilute 
sulfuric acid to give cyclohexanol, which can then be 
used in a Williamson ether synthesis, together with ethyl 
iodide, to give the desired product: 
 
 
 
(b) The desired transformation involves an anti addition 
of OH and OMe across a  bond. This can be achieved 
by converting cyclohexene into an epoxide (upon 
treatment with a peroxy acid), followed by a ring 
opening reaction. The second step of this process 
(opening the ring) can be performed under either acidic 
conditions or basic conditions. 
 
 
 
(c) The desired transformation involves addition of H 
and OR across a  bond. This can be achieved via 
alkoxymercuration-demercuration, where (CH3)3COH is 
used as the alcohol during the alkoxymercuration step. 
 
 
 
 
13.30. 
(a) There are four CO bonds, and each of them is 
cleaved under acidic conditions and replaced with a CI 
bond, giving two moles of compound A and two moles 
of water. 
 
 
(b) As seen in the previous solution (14.34a), two moles 
of compound A are produced for every one mole of 1,4-
dioxane. 
 
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