反应详情

温度

50 °C

To a solution of 4-formyl-2-methyl-benzoic acid tert-butyl ester (Example 4.2) (1.57 g) in tetrahydrofuran/water (3:1) (20 ml) was added sodium acetate (0.67 g) and N-methyl-hydroxylamine hydrochloride (0.69 g). The reaction mixture was stirred at 50° C. for 15 hours. The reaction mixture was diluted with ethyl acetate and water. The phases were separated and the organic layer was washed with water, dried over sodium sulfate and concentrated. The residue was purified by column chromatography on silica gel (eluent: methanol/ethyl acetate 5:5) to give (4-tert-butoxycarbonyl-3-methyl-benzylidene)-N-methyl-nitrone (1.43 g) as yellow oil. 1H-NMR (CDCl3, 400 MHz): 8.10 (s, 1H), 8.02 (d, 1H), 7.85 (d, 1H), 7.35 (s, 1H), 3.90 (s, 3H), 2.60 (s, 3H).

1. customThe phases were separated
2. washthe organic layer was washed with water
3. dry with materialdried over sodium sulfate
4. concentrationconcentrated
5. customThe residue was purified by column chromatography on silica gel (eluent: methanol/ethyl acetate 5:5)