Table 2.
Optimization of the substitution reaction.
 | |||||
| Entry | equiv BnNH2 | Base (equiv) | Conditions | Conversiona | cis/trans-11 ratio |
| 1 | 3 | – | toluene, 16 h, reflux | 100 | 78:22 |
| 2 | 1 | K2CO3 (1.2) | vbm, 1 h, 25 Hz | 40 | 96:04 |
| 3 | 1 | K2CO3 (3) | vbm, 1 h, 25 Hz | 62 | 98:02 |
| 4 | 1.1 | Cs2CO3 (3) | vbm, 1 h, 25 Hz | 74 | 91:09 |
| 5 | 1.1 | Cs2CO3 (3) | vbm, 1 h, 30 Hz | 82 | 94:06 |
| 6 | 1.1 | K2CO3 (3) | vbm, 1 h, 30 Hzb | 49 | 98:02 |
| 7 | 1.1 | Cs2CO3 (3) | vbm, 1 h, 30 Hzb | 59 | 87:13 |
| 8 | 1.3 | K2CO3 (2.2) | pbm, 2 h, 500 rpmb | 97 | 97:03 |
aMeasured by 1H NMR bEtOAc was used as liquid grinding assistant.