60
X. Feng et al.
Table 2.22 Asymmetric hydrogenations of enones 56
B(p-HC 6 F 4 ) 3 (10 mol %)
oxazoline 55b (20 mol %)
H 2 (40 bar)
N
O
Ph
O
R
R'
O
R
R'
55b
56
57
entry product
yield (%) ee (%)
1
57a
O
Ph
94
77
2
57b
O
CF 3
94
80
3
57c
O
F
94
78
4
57d
O
Br
91
71
5
57e
O
Ph
Me
94
86
6
57f
O
Ph
Br
97
85
7
57g
O
Ph
Br
96
68
8
57h
O
Ph
Br
94
69
9
57i
O
Br
COOMe
95
87
10
57j
O
Br
Me
99
86
11
57k
O
Br
Et
99
92