Table 2.
Dependence on the stoichiometric amount of propiophenone (1a) enolate with regard to the metal (reaction time: 2 h, reaction temperature: 25 °C, 5a/6a in %).
| Entry | Metal chloride | Amount of propiophenone (1a) | |||||||
| 2 equiv | 3 equiv | 4 equiv | 6 equiv | ||||||
| 5a | 6a | 5a | 6a | 5a | 6a | 5a | 6a | ||
| 1 | ZrCl4 | 33 | 48 | 76 | 23 | 68 | 22 | – | – |
| 2 | SnCl4 | 20 | 45 | 14 | 35 | 36 | 22 | – | – |
| 3 | AlCl3 | – | – | 66 | 8 | – | – | 66 | 34 |
| 4 | InCl3 | – | – | 85 | 13 | – | – | >99 | – |