反应详情

温度

80 °C

A mixture of 154 (40 g, 154 mmol), SnCl2.2H2O (208 g, 920 mmol), EtOAc (300 mL) and EtOH (150 mL) was heated to 80° C. for 12 h, cooled to RT, poured into crushed ice (2 Kg) and the pH adjusted to pH 7-8 with solid NaHCO3. The solid was filtered and washed with EtOAc. The filtrate was thrice extracted with EtOAc. The combined extracts were washed with brine, dried (Na2SO4), filtered and concentrated in vacuo. The crude product was purified by SiO2 chromatography eluting with an EtOAc/hexane gradient (10 to 50% EtOAc) to afford 28 g (91%) of 4-bromo-3-methyl-1,2-benzenediamine (156) as a brown oil: MS (ESI) m/z=202 [M+1]+.

1. temperaturecooled to RT
2. additionpoured
3. filtrationThe solid was filtered
4. washwashed with EtOAc
5. extractionextracted with EtOAc
6. washThe combined extracts were washed with brine
7. dry with materialdried (Na2SO4)
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customThe crude product was purified by SiO2 chromatography
11. washeluting with an EtOAc/hexane gradient (10 to 50% EtOAc)