Biomedical Engineering Reference
In-Depth Information
N
R
3
O
2
C
CO
2
R
3
CO
2
R
3
N
O
organocatalysis
R
1
+
NN
O
R
1
R
2
R
3
O
2
C
R
2
H
N
Cbz
N
Cbz
Catalyst:
Product:
Me
OH
CO
2
H
H
Me
2
141
99%, ee = 96%
(after NaBH
4
reduction)
H
N
O
EtO
2
C
Bn
CO
2
Et
N
CO
2
Et
+
NH
O
N
Bn
CO
2
Et
Me
142
(ee = 98%)
143
92%
(
142
/
143
= 82:18)
SCHEME 6.29
Proline-catalyzed
a
-amination of aldehyde and ketone.
F
3
C
CF
3
CF
3
1.
H
Cbz
OTMS
CF
3
O
HN
ent
-
76
(10 mol%)
O
Me
O
Me
N
CbzN=NCbz
CH
2
Cl
2
, rt, 30 min;
NaBH
4
, MeOH
O
O
O
O
11
7
H
145
2. K
2
CO
3
,
Toluene, reflux
94%
146
(de = 84%)
H
H
10
1. Grubbs I
CH
2
Cl
2
, RT
Me
Me
Me
11
OMe
N
N
N
2. H
2
, Pd/C
EtOH, rt
7
O
H
H
H
O
O
6
O
HO
HO
149
148
147
H
10
Me
α
-Amination
N
H
H
N
O
6
H
4
Cernuine (
144
)
SCHEME 6.30
Synthesis of the C6-C15 unit of cernuine via
a
-amination.
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