Table 1 Optimization of various reaction conditions^a

1

-/ r. t./ (Nano-SiO₂/AEP (0.01))

60

49

2

-/ r. t./ (Nano-SiO₂/AEP (0.02))

60

53

3

-/ r. t./ (Nano-SiO₂/AEP (0.03))

45

68

4

-/ r. t./ (Nano-SiO₂/AEP (0.035))

25

87

5

-/ r. t./ (Nano-SiO₂/AEP (0.04))

5

95

6

-/ r. t./ (Nano-SiO₂/AEP (0.05))

30

90

7^c

-/ 80/ (Nano-SiO₂/AEP (0.04))

80

68

8^c

-/ 70/ (Nano-SiO₂/AEP (0.04))

70

73

9^c

-/ 50/ (Nano-SiO₂/AEP (0.04))

35

89

10^c

H₂O/ r. t./ (Nano-SiO₂/AEP (0.04))

120

50

11^c

EtOH/ r. t./ (Nano-SiO₂/AEP (0.04))

120

49

12^c

H₂O/EtOH/r. t./(Nano-SiO₂/AEP (0.04))

120

70

13^c

MeOH/ r. t./ (Nano-SiO₂/AEP (0.04))

120

67

14^c

CH₃CN/ r. t./ (Nano-SiO₂/AEP (0.04))

120

56

15

-/ r. t./ -

120

Trace

16

-/ r.t./ (Nano-SiO₂ (0.04))

120

Trace

17

-/ r.t./ (Nano-SC (0.04))

120

Trace