Chemistry Reference
In-Depth Information
11.40
The reaction involves an S
N
2 ring opening of ethylene oxide.
base
(CH
3
)
3
+
CH
2
CH
2
O
-
(CH
3
)
3
N
H
2
O
H
2
C
CH
2
O
(CH
3
)
3
+
CH
2
CH
2
OH ]
-
[
OH
choline
11.41
O
(CH
3
)
3
+
CH
2
CH
2
OH ]
-
C
H
3
C
S
C
oA
+
[
O
O
HC C
+
(CH
3
)
3
-
C
H
3
C
O
HO+ SC oA
H
11.42
Alkyl diazonium salts can lose nitrogen to give 1
o
, 2
o
, or 3
o
carbocations, depending
on the nature of the alkyl group.
N
+
R
+
R
+N
2
Aryl cations are less stable than 1
o
, 2
o
, or 3
o
carbocations, so aryl diazonium salts
are more stable than alkyl diazonium salts.
11.43
These equations illustrate the reactions in Secs. 11.12 and 11.13.
a.
1. HBF
4
N
2
+
HSO
4
-
H
3
C
2. heat
H
3
C
F
+N
2
+
H
2
O
4
b.
heat
N
2
+
HSO
4
-
H
3
C
+
H
O
(see eq. 11.33)
H
3
C
OH
+
N
2
+
H
24
S
O
c.
Cu
2
(CN)
2
N
2
+
HSO
4
-
H
3
C
+
KCN
(see eq. 11.33)
H
3
C
CN
+
N
2
+
KHSO
4
d.
Since
para
coupling is blocked by the methyl substituent,
ortho
coupling
occurs:
