Table 1.
Entry | ArX | 6 | Catalyst | mol % | Temp (°C) | Yield (%)a |
---|---|---|---|---|---|---|
1 | 4 | 6a | Pd(PPh3)4 | 20 | rt | 3a, trace |
2 | 5 | 6a | Pd(PPh3)4 | 20 | rt | 3a, trace |
3 | 5 | 6a | Pd2(dba)3/P(o-tol)3 | 20 | rt | 3a, 0 |
4 | 5 | 6a | PdCl2(dppe) | 20 | rt | 3a, 12 |
5 | 5 | 6a | PdCl2(dppp) | 20 | rt | 3a, 15 |
6 | 5 | 6a | PdCl2(dppb) | 20 | rt | 3a, trace |
7 | 5 | 6a | PdCl2(dppf) | 20 | rt | 3a, 0 |
8 | 5 | 6a | PdCl2(BINAP) | 20 | rt | 3a, 7 |
9 | 5 | 6a | Pd2(dba)3/Xantphos | 20 | rt | 3a, trace |
10 | 5 | 6a | PdCl2(dppp) | 20 | 60 | 3a, 24 |
11b | 5 | 6a | PdCl2(dppp) | 40 | 60 | 3a, 42 |
12b | 5 | 6a | PdCl2(dppp) | 40 | 40 | 3a, 41 |
13b,c | 5 | 6a | PdCl2(dppp) | 40 | 40 | 38,46d |
14 b,c | 5 | 6b | PdCl2(dppp) | 40 | 40 | 3b, 54d |
15b,c | 5 | 6c | PdCl2(dppp) | 40 | 40 | 3c, 31d |
16b,c | 5 | 6d | PdCl2(dppp) | 40 | 40 | 3d, 23d |
0.1 mmol of 4 or 5 was used for entries 1 – 12. 6a(R = Bn), 6b (R = Mes), 6c (R = Bzh) & 6d (R = 1-ad).
1H NMR yield estimated with 1,1,2,2-tetrachloroethane as an internal standard unless otherwise noted.
4.8 equiv of 6, TBAF·3H2O, and Ag2O.
1 mmol scale reaction.
Isolated yield after flash chromatography on silica gel.