反应详情

温度

0 °C

A solution of NaNO2 (4.14 g, 60 mmol) in H2O (15 mL) was added dropwise at 0° C. to a mixture of 3-(trifluoromethyl)aniline (6.24 mL, 50 mmol) and 6 M HCl aqueous solution (50 mL, 300 mmol). After stirring for 15 min, the resulting aqueous solution was added to a suspension of methyl 4-methoxyacetoacetate (7.31 mL, 50 mmol) and NaOAc (24.6 g, 300 mmol) in EtOH (80 mL) pre-cooled at 0° C. The precipitate was collected by filtration, washed with water, and dissolved in AcOEt. The organic solution was washed with water and brine, dried over Na2SO4, and concentrated under reduced pressure. The residue was crystallized from hexane/AcOEt to give the title compound (14.0 g, 88% yield) as pale yellow crystals: 1H NMR (300 MHz, CDCl3): δ ppm 3.51 (3H×0.36, s), 3.52 (3H×0.64, s), 3.90 (3H×0.36, s), 3.94 (3H×0.64, s), 4.68 (2H×0.64, s), 4.70 (2H×0.36, s), 7.41-7.59 (3H+1H×0.64, m), 7.71 (1H×0.36, s), 13.00 (1H×0.64, s), 14.87 (1H×0.36, s).

1. filtrationThe precipitate was collected by filtration
2. washwashed with water
3. dissolutiondissolved in AcOEt
4. washThe organic solution was washed with water and brine
5. dry with materialdried over Na2SO4
6. concentrationconcentrated under reduced pressure
7. customThe residue was crystallized from hexane/AcOEt