2 Frustrated Lewis Pair Catalyzed Asymmetric Reactions
65
Table 2.26 Asymmetric hydrosilylation of 1,2-diketones 60
Ar
O
1. chiral diyne 52a (5 mol %)
HB(C 6 F 5 ) 2 10 (10 mol %)
Cy 3 P (10 mol %)
PhMe 2 SiH (3.0 equiv)
Ar
HO
O
R
O
R
2. Py HF
H
60
61
entry product
yield (%) ee (%)
1
61a
Ph
HO
O
Ph
H
91
>99
2
61b
HO
O
H
F
F
89
99
3
61c
HO
O
H
OMe
OMe
98
99
4
61d
HO
O
H
t Bu
t Bu
96
96
5
61e
Ph
HO
O
OEt
H
96
98
6
61f
HO
O
OEt
H
Me
82
96
7
61g
HO
O
OEt
H
Cl
90
98
8
61h
HO
O
OEt
H
Me
82
>99
9
61i
HO
O
OEt
H
S
87
97