反应详情

The solution of 8-3 (273.4 g, 0.963 mol) dissolved in concentrated H2SO4 (1.6 L) at 0° C. The mixture of conc.HNO3 (63.2 mL) and conc. H2SO4 (400 mL) was added dropwise over 1 h. The color of the reaction became orange. TLC monitored the starting material was disappeared. The reaction mixture was poured onto crushed ice and extracted with ethyl acetate (800 mL×3). The combined organic layers were combined and were concentrated in vacuo to 400 mL, which was cooled under ice bath to afforded 8-4 (234.2 g, 73.9%) as a white solid.

1. additionThe mixture of conc
2. additionThe reaction mixture was poured
3. customonto crushed ice
4. extractionextracted with ethyl acetate (800 mL×3)
5. concentrationwere concentrated in vacuo to 400 mL, which
6. temperaturewas cooled under ice bath