反应详情

Combine benzyl-[2-(4-hydroxy-phenyl)-ethyl]-carbamic acid tert-butyl ester (2.7 g, 8.3 mmol), 4-fluoronitrobenzene (1.2 g, 8.3 mmol), cesium carbonate (5.4 g, 16.6 mmol), and N,N-dimethylformamide (70 mL), stir at room temperature overnight. Pour the reaction into brine then extract with ethyl acetate (3×100 mL). The combined ethyl acetate extracts were dried over sodium chloride/magnesium sulfate, filtered, and concentrated on a rotary evaporator to yield the crude product (3.5 g). The crude product was purified by flash column chromatography on silica gel eluting with ethyl acetate and hexanes to yield benzyl-{2-[4-(4-nitro-phenoxy)-phenyl]-ethyl}-carbamic acid tert-butyl ester (2.7 g): 1H NMR (CDCl3, 300.00 MHz): 8.22 (d, 2H, J=9.2 Hz), 7.44-6.95 (m, 11H), 4.44 (m, 2H), 3.44 (m, 2H), 2.84 (m, 2H), 1.52 (m, 9H). Step 4 {2-[4-(4-Amino-phenoxy)-phenyl]-ethyl}-benzyl-carbamic acid tert-butyl ester

1. additionPour
2. extractionthen extract with ethyl acetate (3×100 mL)
3. dry with materialThe combined ethyl acetate extracts were dried over sodium chloride/magnesium sulfate
4. filtrationfiltered
5. concentrationconcentrated on a rotary evaporator
6. customto yield the crude product (3.5 g)
7. customThe crude product was purified by flash column chromatography on silica gel eluting with ethyl acetate and hexanes