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O
O
O
O
P
HN
O
P
H 2 N
PCl ( 2 equiv)
O
O
O
O
OH
O
CHO
OH
O
Toluene, Py, 80 o C
O
O
H
20a - f
D-xylo
HO
H
O
H
OH
O
O
P
HN
CH 2 OH
PCl ( 2 equiv)
H 2 N
O
O
O
D-xylose
O
O
Toluene, Py, 80 o C
O
OH O
O
O
P
21a - f
D-ribo
O
O
O
O
O
O
P
P
PCl ( 2 equiv)
HO
O
O
O
O
NH 2
NH
CHO
OH
O
O
Toluene, Py, 80 o C
H
O
O
HO
H
22a - f
D-xylo
H
OH
O
O
H
OH
O
P
CH 2 OH
HO
PCl ( 2 equiv)
O
O
O
O
D-glucose
O
Toluene, Py, 80 o C
O
NH 2 O
NH O
O
P
23a - f
D-ribo
O
R 1
R 2
R 1
O
O
O
=
O
O
O
R 1
R 2
R 1
a R 1 = R 2 = t Bu
b R 1 = t Bu; R 2 = OMe
c R 1 = SiMe 3 ; R 2 = H
d R 1 = R 2 = Me
e ( R ) ax ; R 1 = SiMe 3
f ( S ) ax ; R 1 = SiMe 3
Scheme 10.9 Synthesis of furanoside
phosphite-phosphoroamidite ligands 20-23:
(i) I 2 /acetone (95% yield); (ii) H 2 SO 4 /CH 3 OH
(90% yield); (iii) TsCl/CH 2 Cl 2 /Py, − 20 °C to
room temp. (89% yield); (iv) NaN 3 /DMF
(96% yield); (v) PPh 3 /THF/H 2 O (92% yield);
(vi) PCC/AcONa/CH 2 Cl 2 then NaBH 4 /EtOH/
H 2 O, − 15 °C (74% yield); (vii) PPh 3 /THF/H 2 O
(90% yield); (viii) I 2 /acetone (98% yield); (ix)
− 15 °C (82% yield); (x) Tf 2 O/Py/CH 2 Cl 2 ,
− 10 °C (76% yield); (xi) NaN 3 /BuNCl/DMF,
50 °C (86% yield); (xii) AcOH/H 2 O then
NaIO 4 /NaHCO 3 /H 2 O (85% yield); (xiii)
NaBH 4 /EtOH then PPh 3 /THF/H 2 O (82%
yield); (xiv) Tf 2 O/Py/CH 2 Cl 2 , − 10 °C (98%
yield); (xv) NaN 3 /BuNCl/DMF, 50 °C (70%
yield); (xvi) AcOH/H 2 O then NaIO 4 /
NaHCO 3 /H 2 O (91% yield); (xvii) NaBH 4 /
 
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