S. No. | Condition | Time (min) | Yield (%)(a) |
1 | No sonication | 30 | 45 |
2 | No sonication | 45 | 55 |
3 | Sonication at R.T. | 10 | 60 |
4 | Sonication at R.T. | 20 | 80 |
5 | Sonication at R.T. | 30 | 96 |