Chemistry Reference
In-Depth Information
SO
2
Cl
1)
Toluene, 110°C, 24 h
(MeO)
3
Si
SO
3
H
O
O
SiO
2
SiO
2
O
Si
2) 2 N H
2
SO
4
, 12 h
Silica-PhSO
3
H
Ion exchange capacity: 0.57 mmolH
+
/g
SO
3
Na
1) 1 N NaCl aq., 1 h
O
O
SiO
2
O
Si
2) Neutralize to pH = 7.0
by 0.1 N NaOH aq.
Silica-Na
SO
3
Sc(OTf)
2
Sc(OTf)
3
EtOH, 80°C, 20 h
O
O
SiO
2
O
Si
Silica-Sc
4
Scheme 1.15.
Silica-Sc
4
(0.27 mmol/g, 5.4 mol %)
[DBIm]SbF
6
(30 wt %)
Solvent
15°C, 24 h
OSiMe
3
SEt
OH
O
+
PhCHO
Ph
SEt
5
Solvent: Et
2
O 22% yield
Hexane 26% yield
H
2
O 97% yield
H
2
O without Silica-Sc 0% yield
H
2
O without IL 31% yield
neat 25% yield
Scheme 1.16.
Water
Substrates
+
-
Ionic liquid
+
SO
3
Sc(OTf)
2
-
+
-
+
-
+
-
+
+
-
SO
3
Sc(OTf)
2
-
+
+
-
-
-
+
+
-
-
+
-
+
+
+
-
+
+
-
+
-
Product
Si
Si
-
+
-
O
O
O
-
+
-
O
O
O
+
-
Silica supporting material
Scheme 1.17.
