425 / 912
Chapter 12 417
Copyright © 2017 Pearson Education, Inc.
2.
The product has two asymmetric centers.
Because addition of Br
2
is anti, only the stereoisomers with the bromine atoms on opposite sides of
the ring are obtained.
CH
3
Br
Br
H
3
C
Br
Br
3.
The product does not have an asymmetric center, so it does not have stereoisomers.
H
3
C Br
4.
The product has two asymmetric centers.
Because radical addition of HBr can be either syn or anti, four stereoisomers are obtained as products.
CH
3
Br
CH
3
Br
H
3
C
Br
H
3
C
Br
23.
a.
Br
Br
2
hv
tert
-BuO
−
RCOOH
O
2
Br
Br
2
hv
Br
Br
2
hv
Br
Br
2
hv
tert
-BuO
−
RCOOH
O
3
2
HO
−
HO
−
NaOCl
CH
3
COOH
0
°
C
NaOCl
CH
3
COOH
0
°
C
O
HO
−
H
b.
r
O
Br
2
hv
tert
-BuO
−
RCOOH
CH
2
r
Br
2
hv
r
Br
2
hv
Br
Br
2
hv
tert
-BuO
−
RC O
CH
3
CH
2
OH
C
O
O
−
O
−
NaOCl
CH
3
C OH
0
°
C
aOCl
CH
3
COO
0
°
C
OH
O
H
−
OH
OH
H
c.
Br
Br
v
er
B O
−
RC H
2
B
Br
2
hv
r
B
Br
2
er
-BuO
−
CO
2
OH
H
H
−
a
CH C
C
N C
H H
C
O
O
−
d.
B
Br
v
tert
B O
C
O
2
B
2
hv
r
r
v
t
-BuO
C H
O
3
2
HO
a l
C C
C
N O
H C H
0 C
O
H
24.
Four atoms (three carbons and one oxygen) share the unpaired electrons.
.
O
OH
O
OH
O
OH
OH
O
.
OH
O
.
.
.