Entry | Mole ratio of 1/2 | Halogen source | Solvent | Condition | Time | Yielda (%) |
1 | 1:2 | NCS | CH3CN | Air | 10 h | 98 |
2 | 1:1.2 | NBS | CH3CN | Air | 20 min | 95 |
3 | 1:0.6 | TCCA | CH3CN | N2 | 6 h | 87 |