反应详情

N1-(9H-9-fluorenyl)-4-(benzyloxy)-5-methoxy-2-nitrobenzamide of formula (7e) (500 mg, 1.07 mmol) was dissolved in methanol (10 mL), SnCl2.2H2O (839 mg, 3.2 mmol) was added and refluxed until the TLC indicated the completion of the reaction. The methanol was evaporated by vacuum and the aqueous layer was then adjusted to pH 8 with 10% NaHCO3 solution and extracted with ethyl acetate (2×30 mL). The combined organic phase was dried over Na2SO4 and evaporated under vacuum to afford the crude N1-(9H-9-fluorenyl)-2-amino-4-(benzyloxy)-5-methoxybenzamide (450 mg, 95% yield). This was further purified by column chromatography using ethyl acetate:hexane (6:4) as a solvent system to obtain the pure product (8e) (610 mg, 84% yield). 1H NMR (CDCl3) δ 3.95 (s, 3H), 5.20 (s, 2H), 5.70 (s, 1H), 6.70 (s, 1H), 7.00-7.41 (m, 5H), 7.45-7.706 (m, 9H); FABMS: 436 (M+H)+.

1. temperaturerefluxed until the TLC
2. customthe completion of the reaction
3. customThe methanol was evaporated by vacuum
4. extractionextracted with ethyl acetate (2×30 mL)
5. dry with materialThe combined organic phase was dried over Na2SO4
6. customevaporated under vacuum
7. customto afford the crude N1-(9H-9-fluorenyl)-2-amino-4-(benzyloxy)-5-methoxybenzamide (450 mg, 95% yield)
8. customThis was further purified by column chromatography