反应详情

温度

-78 °C

To a solution of N-acetyl-3-bromo-4-methylaniline (1.43 g, 627 mmol) in THF (50 mL) at −78° C. is added 2M BuLi in pentane (7.83 mL, 15.66 mmol) dropwise. After a further 1 h, diethyl oxalate (4.26 mL, 31.3 mmol) is added. After stirring for 4 hours at −78° C., the reaction mixture is quenched with saturated NH4Cl solution. The mixture is partitioned between ethyl acetate and water. The layer is separated and the aqueous layer is extracted with ethyl acetate. The combined organic extracts are washed with brine, dried over Na2SO4, filtered and concentrated. The residue is purified by column chromatography (silica gel, eluting with ethyl acetate; hexanes from 1/1 to 2/1) to afford fee title compound (0.82 g, 52%).

1. customthe reaction mixture is quenched with saturated NH4Cl solution
2. customThe mixture is partitioned between ethyl acetate and water
3. customThe layer is separated
4. extractionthe aqueous layer is extracted with ethyl acetate
5. washThe combined organic extracts are washed with brine
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated
9. customThe residue is purified by column chromatography (silica gel, eluting with ethyl acetate; hexanes from 1/1 to 2/1)