Chemistry Reference
In-Depth Information
R
2
R
2
NH
O
NH
O
Rh(I)-L
R
1
R
1
∗
X
X
H
2
Rhodium-catalyzed hydrogenation of (
E
)- and (
Z
)-
β
-dehydroamino acid derivatives
O
Cu(OTf)
2
(10 mol%)
(A)
(10 mol%)
CH
2
Cl
2
, -20°C
OSiMe
3
H
O
R
3
NH
O
R
1
+
R
3
X
ROOC
N
ROOC
X
R
2
R
1
R
2
Ph
Ph
26 examples
44-96%
(
syn
/
anti
) 52:48 - 99:1
6-96%
ee
Cu-catalyzed addition of sylil enol ethers to
N
-acylimino esters
NH
HN
1-Nap
1-Nap
(A)
NHBoc
Boc
N
(B)
(10 mol%)
CO
2
t
Bu
Ph
N
CO
2
t
Bu
+
R
Ar
H
Cs
2
CO
3
, PhF
Ph
N
Ph
Ph
4-MeO-C
6
H
4
BF
4
-
4-Me-C
6
H
4
10 examples
86-99% (
syn
/
snti
)
95:5-99:1
dr
58-80%
ee
N
O
4-Me-C
6
H
4
+
+
4-Me-C
6
H
4
O
N
4-Me-C
6
H
4
BF
4
-
4-MeO-C
6
H
4
(B)
Mannich reaction catalyzed by a chiral phase transfer catalyst
(a) NaClO
2
, KH
2
PO
4
,
2-methyl-2-butene,
t
Bu, H
2
O
(b) CH
2
N
2
, Et
2
O
PMP
PMP
H
H
O
HN
R
CO
2
Et
O
N
(C)
( 5 mol%)
+
H
CO
2
Et
H
H
CO
2
Et
N
dioxane, 20°C
(d) LHMDS, THF,
-20°C
O
PMP
R
R
7 examples
57-89% (
syn
/
anti
)
52:48-95:5
dr
93-99%
ee
CO
2
H
R=
i
Pr 85%
93%
ee
H
(C)
Proline-catalyzed asymmetric Mannich reaction of aldehydes and
α
-imido carboxylates to yield
β
-lactams
after three consecutive steps
28
NH
3
+
CO
2
-
NH
3
+
[PAM]
R
CO
2
-
R
30°C
8 examples
0-99%
ee
Phenylalanine amino mutase (PAM)-catalyzed synthesis of
-amino acids
29
β
-amino acids from
α
Figure 2.5
Some examples of catalytic asymmetric syntheses of b-amino acids.
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