Chemistry Reference
In-Depth Information
R 1
R 2
a R 1 =R 2 = H
b R 1 = t Bu, R 2 = OMe
c R 1 =R 2 = t Bu
d R 1 = SiMe 3 , R 2 = H
O
O
O
O
O
O
=
O
O
OO P
D- gluco
OOH
a)
O
O
R 1
R 2
11-50%
O O
O O
17
R 3
e ( S ) ax R 3 = H
f ( R ) ax R 3 = H
O
O
59a-f (48% ee for 59f )
O
O
=
O
O
O
R 3
O
O
O
b)
a)
D- allo
O
O
O
92%
O
O
a-d: 12-22%
e-f: 98-99%
O O
O O
O O
O
O
OH
P
22
60
61a-f (57% ee for 61e )
c), d)
65%
O
O
SCu
D- gluco
O
O
O
SCN
e), f)
82%
O
O O
O O
63 (60% ee)
62
O
O
OH
OH
OH
P
D- galacto
g)
O
a)
O
O
O
HO
OH
c: 23%
a-b, d-f:n.d.*
O
O O
OH
O
O O
O
O
D-(+)- galactose
64
65
66a-f (4% ee for 66c )
O
O
a)
O
O
D- fructo
O
O
b,c:28-29%
a,d-f: n.d.*
OH
O
OH
h)
O
OH
O
O
P
O
O
O
O
68
OH
OH
HO
69a-f (12% ee for 69e )
i)
O
D-(-)- fructose
67
O
O
D- fructo
a)
O
OH
O
O
O
O
O
12-15%
O P
O
70
O
O
71c,e,f (33% ee for 71f )
(a) PCl 3 , NEt 3 , THF, biaryl alcohol ( a - f ) *n.d.: yields no described. (b) NaBH 4 , EtOH. (c) Tf 2 O,
pyridine, CH 2 Cl 2. (d) KSCN, CH 3 CN. (e) NaBH 4 , EtOH, H 2 O. (f) BuLi, Et 2 O, hexane. Cu(MeCN) 4 PF 6.
(g) DMF, acetone, Dowex H+. (h) HClO 4 , dimethoxypropane,0 C. (i) HClO 4 , dimethoxypropane, rt.
Scheme 12.12
Synthesis of monodentate P or S-ligands .
 
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