Table 1.
Optimization of Pd-Catalyzed C-3 and Benzylic Arylation of 1aa
| ||||
|---|---|---|---|---|
| entry | base | 3ab (%)a | 4ab (%)a | 5ab (%)a |
| 1 | KN(SiMe3)2 | 93(93)b | 6 | 0 |
| 2 | NaN(SiMe3)2 | <5 | <5 | 29 |
| 3 | LiN(SiMe3)2 | 0 | 0 | 0 |
| 4 | KN(SiMe3)2:18-crown-6c | 0 | 13 | 51 |
| 5 | NaN(SiMe3)2:l5-crown-5c | 0 | <5 | 39 |
| 6 | LiN(SiMe3)2:12-crown-4c | 0 | 0 | 94(91)b |
Yield determined by 1H NMR spectroscopy of the crude reaction mixture.
Isolated yield after chromatographic purification.
Crown ether (2 equiv relative to base) employed.