Bruice - Chimica Organica

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640 Chapter 18
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d.
2. H2O
Br2
FeBr3
C
CH3
O
Br
CH 3CH2 Br
H2 Pd/C
(CH3 )3 CCl
CH3CH 2 Br
C(CH 3)3
AlCl3
1. CH3 CCl
O
AlCl3
C
CH 3
O
92. a. The first three compounds will not show a carbonyl stretch at 1700 cm -1 , and the bottom four will
show this absorption band. The first three can be distinguished from one another by the presence or
absence of the indicated absorption bands.
CH2 OH CH 2OH CH2OCH3
band at 3300 cm-1 band at 3300 cm- 1 no band at 3300 cm- 1
no band at 1600 cm- 1 band at 1600 cm- 1 band at 1600 cm- 1
The last four compounds all have an absorption band at 1700 cm-1.
They can be distinguished by the presence or absence of the indicated absorption bands.
C
OH
O
C
H
O
C
OCH
O
3
C
CH
O
3
large broad band at no band at no band at no band at
25009 3500 cm-1 250093500 cm - 1 250093500 cm -1 250093500 cm- 1
band at 1250 cm-1 no band at 1250 cm-1 band at 1250 cm- 1 no band at 1250 cm- 1
no band at 2700 cm- 1 band at 2700 cm-1 no band at 2700 cm-1 no band at 2700 cm- 1
b. This is the only compound without the characteristic benzene ring hydrogens at 7 -8 ppm.
CH2OH
Only two compounds will have two signals other than the signals for the benzene ring hydrogens. They can
be distinguished by integration (2:3 versus 2:1) or by the two sharp singlets for the ether versus the some-
what broader singlet for the hydrogen bonded to oxygen.
CH 2 3 OCH CH2OH