反应详情

温度

-5 °C

To a suspension of 3-amino-5-nitrobenzyl alcohol (103.8 g, 0.62 mol; from step (ii) above) in 1.0 L of 6N HCl at −5° C. was added sodium nitrite (47.1 g, 0.68 mol) in H2O (400 mL) over 45 min. The resulting solution was stirred at −5° C. for 1 h prior to the addition of a mixture of copper(II)chloride (125.0 g, 0.93 mol) and copper(I)chloride (0.74 g, 0.007 mol) in 6N HCl (1.0 L) over 1 h while maintaining the temperature at less than 0° C. The resulting solution was warmed to 60-70° C. for 2.5 h then cooled to room temperature and extracted with Et2O (6×). The organics were washed with brine (2×), dried (Na2SO4), filtered and concentrated in vacuo to give the crude product. Flash chromatography on silica gel eluting with Hex:EtOAc (4:1) gave 81.7 g (70%) of the sub-title compound as an off white solid. The sub-title compound could be further purified by crystallization from CH2Cl2.

1. temperaturewhile maintaining the temperature at less than 0° C
2. temperatureThe resulting solution was warmed to 60-70° C. for 2.5 h
3. temperaturethen cooled to room temperature
4. extractionextracted with Et2O (6×)
5. washThe organics were washed with brine (2×)
6. dry with materialdried (Na2SO4)
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customto give the crude product