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O O
c)
Ph 2 PO
D- xylo
D- ribo
68%
BzO
HO
14 (32% ee)
HO
OH
a)
b)
O
O
O
94%
90%
O O
O O
O O
O
OH
2
12
D- ribo
13
O
R 1
R 2
d)
P
O
O
O
O
O
O
O
=
45-54%
O
O O
O
R 1
R 2
P
O
15 a-c
(8% ee for 15a )
a R 1 =R 2 = H
b R 1 = t Bu, R 2 = OMe
c R 1 =R 2 = t Bu
(a) 1. BzCl, NEt 3 , CH 2 Cl 2. 2. PCC, NaOAc, CH 2 Cl 2. (b) 1. NaBH 4 , EtOH. 2. NaOMe,
MeOH. (c) PPh 2 Cl, pyridine, DMAP. (d) (RO) 2 PCl, pyridine, toluene.
Scheme 12.5
Synthesis of bidentate P,P ribo ligands.
D- gluco
O
O
TsO
HO
O
HO
OO P
HO
OAc
P
HO
OAc
OH
f)
d)
e)
O
O
O
O
13
O
92%
81%
71-74%
O O
O O
O O
O O
20
18
19
21 (84% ee for 21g )
b), c)
90%
D- gluco
O
HO
OOH
R 3
R 1
R 2
O
a)
e ( S ) ax R 3 = H
f ( R ) ax R 3 = H
g ( S ) ax R 3 = SiMe 3
h ( R ) ax R 3 = SiMe 3
a R 1 =R 2 = H
b R 1 =R 2 = t Bu
c R 1 = t Bu, R 2 = OMe
d R 1 = SiMe 3 , R 2 = H
HO
O
O
O
O
O =
HO
OH
96%
O
O
O
O
=
OH
O O
17
D-(+)-glucose
16
R 1
R 2
R 3
g)
98%
O
O
O
D- Allo
TsO
O
O O
O
HO
HO
P
O
e)
f)
O
O
O
O
22
92%
50-65%
O O
O O
O
O
O O
AcO
OH
h),i), j)
O
80%
P
d)
HO
24
25
HO
81%
26 (3% ee for 26b )
O
O O
AcO
L- talo
23
O
c),b)
AcO
O
P
TfO
OH
O
45%
O
e)
f)
O
O
78%
O
O
O O
50-67%
O
O O
O O
P
AcO
OH
27
28
29 (5% ee for 29b )
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