system also worked well for imide, amide, phthalimide, and sulfonamide yielding
decent yield of the N-arylated product.
The scope of this catalytic system was even extended for the amination of
aromatic amines with boronic acids using DMSO as solvent and KOH as base at
Table 39 Amination of iodobenzene by aniline using heterogenized copper complexes
Sr.
No. Catalyst
Aniline
Conv (%)
DPA
selectivity
(%)
DPA
yield (%)
TPA
yield (%)
DPA/TPA
ratio
a
Cu(Phen or Bipy) complex
encapsulated in NaY
b
1
Na–Y
40
58
23
8
2.9
c
2
4% Cu–Y
60
69
41
7
5.9
b
3
1% Cu(Phen)–Y
85
80
68
4
17.0
c
4
4% Cu(Phen)–Y
88
84
74
3
24.7
c
5
4% Cu(Bipy)–Y
89
87
78
2
39.0
d
6
8% Cu(Phen)–Y
90
66
60
15
4.0
e
Cu(Bipy) complex
encapsulated in MCM-41
7
MCM-41
18
16.6
3
6
0.5
8
4% Cu-MCM-41
32
28.1
9
15
0.6
9
4% Cu(Bipy)-MCM-41
80
6.3
5
71
7.0
f
4% Cu(Phen or neocup)(PPh3)
Br complex tethered catalyst
10 Cu(Phen)(PPh 3 )
Br-PTA-Y
86
10.5
9
72
0.1
11 Cu(neocup)(PPh 3 )BrPTA-Y
70
15
10.5
60
0.2
12 Cu(Phen)(PPh 3 )Br-PTAalumina
78
10.2
8
55
0.15
13 Cu(Phen)(PPh 3 )Br-PTAtitanium oxide
74
17.6
13
26
0.5
14 Cu(Phen)(PPh3)Br-PTAclay
80
8.8
7
32
0.2
15 Cu(Phen)(PPh3)Br-PTAcharcoal
50
48
24
25
0.96
16 Cu(Phen)(PPh3)Br-PTAsilica
56
35.7
20
22
0.9
a
Iodobenzene: 2.0 mmol; aniline: 2.1 mmol; KOt-Bu: 6.4 mmol; toluene: 20 ml; temperature
408 K; time: 14 h
b
Catalyst 900 mg
c
Catalyst 225 mg
d
Catalyst 115 mg
e
Iodobenzene: 2.0 mmol; aniline: 2.1 mmol; KOt-Bu: 6.4 mmol; 4% Cu(Bipy)-MCM-41: 225 mg;
toluene: 20 ml; temperature: 408 K; time: 14 h
f
Iodobenzene: 8.2 mmol; aniline: 4.0 mmol; KOt-Bu: 16.0 mmol; 4% Cu catalysts: 550 mg;
toluene: 20.0 ml; naphthalene (IS); 0.25 g; temperature: 385 K; time: 10 h
Recent Developments in Recyclable Copper Catalyst Systems for C–N Bond. . .
167