Biomedical Engineering Reference
In-Depth Information
(
R
,
R
)-
5d
18-crown-6
(0.05 mol% each)
O
O
+
CPh
2
N
Ph
2
C
N
PhCH
2
Br
O
t
-Bu
O
t
-Bu
50% KOH aq
Toluene, 0°C, 3 h
90%
H
Ph
2a
3a
(ee = 98%)
Ar
(4% (w/o 18-crown-6))
-
Br
O
+
O
O
N
O
O
O
Ar
(
R
,
R
)-
5d
(Ar = 3,5-Ph
2
-C
6
H
3
)
18-crown-6
SCHEME 7.4
(
S
)-
17a
(0.01-0.05 mol%
)
O
O
Ph
2
C
N
+
RBr
Ph
2
C
N
O
t
-Bu
O
t
-Bu
50% KOH aq
Toluene
0°C, 2-64 h
81-98%
HR
2a
3
(ee = >97%)
Ar
Br
-
F
F
+
Bu
Bu
N
Ar =
F
Ar
(
S
)-
17a
SCHEME 7.5
catalyst
(10 mol%)
O
O
Ph
2
C
N
+
PhCH
2
Br
Ph
2
C
N
OR
OR
NaOH aq or
CsOH·H
2
O
Toluene
H
Ph
2b
(R =
i
-Pr)
2a
(R =
t
-Bu)
3b
(R =
i-
Pr)
3a
(R =
t-
Bu)
with
18a
;
3b
(90%; ee = 90%)
with
18b
;
3b
(67%; ee = 94%)
-
Cl
+
Cl
-
H
N
+
H
N
O
N
OH
N
18a
18b
SCHEME 7.6
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