Table 2.
| |||||
---|---|---|---|---|---|
Entry | Base | Solvent | temp (°C) | conc. (M) | Yield (%) |
1 | NaOt-Bu | DME | rt | 0.1 | 27 |
2 | NaH | DME | rt | 0.1 | 74 |
3 | KOt-Bu | DME | rt | 0.1 | 63 |
4 | n-BuLi | THF | –78 | 0.1 | n.d. |
5 | n-BuLi | THF | 0 | 0.1 | n.d. |
6 | i-PrMgCl | THF | 0 | 0.1 | 90a |
7 | i-PrMgCl | THF | 0 | 0.2 | 74 |
DME = 1,2-dimethoxyethane