Table 1.
Effect of various catalysts for the preparation of 2-phenylbenzoxazole.a
| Entry | Catalyst | Conversionb (%) |
| 1 | Fe3O4 | 26 |
| 2 | 3-(3-(Trimethoxysilyl)propyl)-1H-imidazole-3-ium chloride | 44 |
| 3 | ZnCl2 | 35 |
| 4 | FeCl3 | 30 |
| 5 | Choline chloride | 41 |
| 6 | LAIL@MNP | 82 |
| 7 | [EMIM]Cl | 31 |
| 8 | [BMIM]BF4 | 43 |
Reaction conditions: 2-Aminophenol (1.0 mmol), benzaldehyde (1.0 mmol), catalysts (4 mg) under solvent-free sonication at 70 °C for 30 min.
Conversion was reported by GC-MS.