反应详情

温度

-40 °C

A solution of 2,4,5-trichloronitrobenzene (Jpn. Kokai Tokyo Koho JP 81,169,651 (1980), Chem. Abstr. 1981,96, 162307 q)(103 g, 0.46 mol) and t-butyl chloroacetate (79 ml, 0.55 mol) in dry tetrahydrofuran (400 ml) was added dropwise over 30 minutes to a solution of potassium t-butoxide (128 g, 1.14 mol) in dry tetrahydrofuran (800 ml) with stirring, under nitrogen keeping the temperature at -40° C. After the addition was complete, the resulting dark blue solution was stirred for a further 30 minutes. The mixture was poured into 0.5M hydrochloric acid (2 L) and the product was extracted into ethyl acetate (2.5L and 1 L). The combined organic solutions were dried (MgSO4) and evaporated onto silica gel (70-200 m, 200 g). The silica gel was applied to the top of a silica gel chromatography column (800 g), and the product was eluted using a hexane/ethyl acetate gradient. Product-containing fractions were combined and evaporated to give a yellow solid, which was triturated with hexane to give t-butyl 2-nitro-3,5,6-trichlorophenylacetate (91.8 g, 59%) as a white solid.

1. additionAfter the addition
2. stirringthe resulting dark blue solution was stirred for a further 30 minutes
3. extractionthe product was extracted into ethyl acetate (2.5L and 1 L)
4. dry with materialThe combined organic solutions were dried (MgSO4)
5. customevaporated onto silica gel (70-200 m, 200 g)
6. washthe product was eluted
7. customevaporated
8. customto give a yellow solid, which
9. customwas triturated with hexane