Entry
Catalyst (mol %)
Reaction conditions
Yield of 4a (%)b
Yield of 6a (%)b
1 - 130 °C, 1 h, air 82 0
2 - DMSO, 130 °C, 1 h, air 64 0
3 - CH3CN, 130 °C, 1 h, air 78 0
4 - THF, 130 °C, 1 h, air 66 0
5c - 130 °C, 1 h, air 51 0
6d - 130 °C, 1 h, air 67 0
7e - 130 °C, 1 h, air 76 0
8 - 120 °C, 1 h, air 70 0
9 - 140 °C, 1 h, air 74 0
10 - 130 °C, 16 h, air 58 8
11 CuCl (20) 130 °C, 16 h, air Trace 66
12 CuBr (20) 130 °C, 16 h, air Trace 39
13 CuI (20) 130 °C, 16 h, air Trace 56
14 CuCl2 (20) 130 °C, 16 h, air Trace 53
15 CuO (20) 130 °C, 16 h, air Trace 55
16 CuCl (5) 130 °C, 16 h, air Trace 40
17 CuCl (20) 130 °C, 16 h, O2 Trace 45
18 CuCl (20) 130 °C, 16 h, N2 71 Trace