反应详情

A solution of chromium(VI) oxide (91 g, 0.919 mol) in a 1:4 water/acetic acid solution is added portionwise to 2-chloro-2'-methoxy-5-nitrobenzhydrol (64.2 g, 0.219 mol) while maintaining the reaction mixture temperature at 25°-35° C. The reaction mixture is then stirred at 25°-35° C. for 1 hour, cooled, diluted with water and concentrated in vacuo to obtain a residue. The residue is diluted with water and extracted with methylene chloride. The organic extracts are combined, dried over anhydrous sodium sulfate, mixed with silica gel (10 g) and filtered. The filtrate is concentrated in vacuo to obtain an oil. A solution of the oil in a methanol/water solution is decolorized with charcoal and concentrated in vacuo to yield a residue. Column chromatography of the residue using silica gel and methylene chloride/hexanes solutions gives the title product as a white solid.

1. temperaturewhile maintaining the reaction mixture temperature at 25°-35° C
2. temperaturecooled
3. concentrationconcentrated in vacuo
4. customto obtain a residue
5. extractionextracted with methylene chloride
6. dry with materialdried over anhydrous sodium sulfate
7. additionmixed with silica gel (10 g)
8. filtrationfiltered
9. concentrationThe filtrate is concentrated in vacuo
10. customto obtain an oil
11. concentrationconcentrated in vacuo
12. customto yield a residue