反应详情

To a suspension of 198 mg (4.53 mmol) of sodium hydride (65% in oil, washed with pentane) in 2.5 ml of dry tetrahydrofuran a solution of 356 mg (3.74 mmol) of 3-hydroxypyridine in 5 ml of tetrahydrofuran is dropped and the mixture stirred for 1 hour at room temperature. After cooling to 0° C. 1.0 g (3.74 mmol) of 5-fluoro-2-nitro-4-trifluoromethyl-benzoic acid methyl ester dissolved in 10 ml of tetrahydrofuran is added and stirring continued for 7 hours. The reaction mixture is diluted with water and extracted with ethyl acetate. The organic phase is washed with brine, dried over Na2SO4 and evaporated to give an oil which is fractionated by medium pressure chromatography on silica with ethyl acetate/cyclohexane 1:1. The fractions containing the product are combined and evaporated yielding 977 mg of 2-nitro-5-(pyridin-3-yloxy)-4-trifluoromethyl-benzoic acid methyl ester as white powder, m.p. 98-100° C.

1. additionis dropped
2. temperatureAfter cooling to 0° C
3. additionis added
4. stirringstirring
5. waitcontinued for 7 hours
6. extractionextracted with ethyl acetate
7. washThe organic phase is washed with brine
8. dry with materialdried over Na2SO4
9. customevaporated
10. customto give an oil which
11. additionThe fractions containing the product
12. customevaporated