反应详情

Zn dust (34.87 g, 533 mmol) was added to a stirred solution of 5-bromo-2-nitro-9H-thioxanthene (28.64 g, 88.9 mmol) in glacial acetic acid (300 ml) at 0° C. (ice bath). After one hour the ice bath was removed and the solution was left to react overnight at room temperature. The mixture was filtered through a pad of Celite and washed with copious amount of dichloromethane and the filtrate was evaporated in vacuo. Water was added (800 ml) to the residue and the pH was adjusted to pH 8 by addition of concentrated ammonia (100 ml). The solid formed was filtered and dried in a vacuum desiccator to give the title compound (26.64 g) and was used without any further purification. m/z (LC-MS, ESP), RT=4.53 min, (M++1)=294-292, (1:1, bromine isotope ratio present)

1. customAfter one hour the ice bath was removed
2. waitthe solution was left
3. customto react overnight at room temperature
4. filtrationThe mixture was filtered through a pad of Celite
5. washwashed with copious amount of dichloromethane
6. customthe filtrate was evaporated in vacuo
7. additionWater was added (800 ml) to the residue
8. additionthe pH was adjusted to pH 8 by addition of concentrated ammonia (100 ml)
9. customThe solid formed
10. filtrationwas filtered
11. customdried in a vacuum desiccator