| Entry | Catalyst (mol %) | Time | Yield (%) |
| 1 | 5 | 120 min | 65 |
| 2 | 10 | 90 min | 78 |
| 3 | 15 | 60 min | 85 |
| 4 | 20 | 25 min | 95 |
| 5 | 25 | 25 min | 95 |
| 6 | 30 | 25 min | 95 |