Table 2.
Optimization on the product yield using Bi(NO3)3·5H2O
| Entry | Solvent | Reaction time (h) | Yield (%) |
|---|---|---|---|
| 1a | ACN | 1.5 | 6.8 |
| 2b | ACN | 1.5 | 10.2 |
| 3 | ACN | 1.5 | 19.6 |
| 4 | CH2Cl2 | 1.5 | 17.1 |
| 5 | Water | 1.5 | 9.1 |
| 6c | Water | 1.5 | 12.0 |
| 7 | Ethanol | 1.5 | 22.2 |
| 8d | ACN | 1.5 | 21.8 |
| 9 | Ethanol | 0.5 | 26.8 |
| 10 | Ethanol | 3 | 25.3 |
| 11 | Ethanol | 7 | 18.6 |
All the reactions were carried out at room temperature and catalyst (0.2 mol equiv) was added
aCatalyst (0.05 mol equiv) was added
bCatalyst (0.1 mol equiv) was added
c0.1 M nitric acid was used and no metal catalyst was added
dThe reaction was carried out under reflux