Entry | Reagents used | Yield | Reaction time | Reaction steps | Remarks | Ref. |
1 | PTC/M2CO3/CH2Cl2, M = K, Na | 45% - 70% | 1 - 4 hrs | 3 | VOC used | [22] |
2 | BF3-SiO2 | 78% - 88% | 1 - 2 mins | 2 | Solvent free | [28] |
3 | Mineral acid, NaOH, CH3COONa | 80% | 3.5 hrs | 3 | VOC used | [31] |
4 | alkali | 54% - 75% | - | 3 | Temp and pH control | [6] |
5 | Amberlite IR120 (Na+), acid, cyclohexane | 65% - 74% | 1 - 2 hrs | 3 | VOC used | [30] |