Table 4.
Entry | Ligand (equiv) | Solvent | Conv. (%)b |
---|---|---|---|
1 | PPh3 (0.2) | 5% DMSO-DMF | 65 |
2 | PPh3 (0.2) | i-PrOH | 56 |
3 | PPh3 (0.2) | xylenes | 78 |
4 | PPh3 (1.0) | 5% DMSO-DMF | 3 |
5 | PPh3 (1.0) | i-PrOH | 8 |
6 | PPh3 (1.0) | xylenes | 39 |
7 | dppe (0.2) | xylenes | 75 |
8 | dppp (0.2) | xylenes | 66 |
9 | dppp (1.0) | xylenes | 41 |
10 | P(O)(octyl)3 (5.0) | 5% DMSO-DMF | 71 |
11 | Pyridine | 5% DMSO-DMF | No Prod |
12 | Bis-sulfoxidec | 5% DMSO-DMF | 66 |
Reaction conditions: initial concentration [6] = 0.10 M and [Pd(O2CCF3)2] = 0.020 M, 10 equiv CF3CO2H, 3.0 mL solvent, 70 °C, 24 h.
GC monitoring of the formation of 8 with biphenyl as internal standard.
Pd(OC2CCF3)2 was replaced with Pd(PhSOCH2CH2SOPh)(OAc)2.