反应详情

A mixture of 3.2 g (7.1 mmole) of 4-(3-chloro-phenyl)-2-(5-dimethoxymethyl-2-nitro-phenylamino)-thiazole-5-carboxylic acid amide (VI.2a), 30 mL of 2M hydrochloric acid and 5 mL of dimethylformamide was stirred at 60 degrees for 3 hours. The mixture was cooled and then concentrated under reduced pressure. The residue was taken up in 100 mL of dichloromethane and washed once with 100 mL of saturated sodium bicarbonate solution, once with 50 mL of brine, and then dried over anhydrous sodium sulfate. The mixture was filtered and concentrated under reduced pressure. The residue was purified by silica gel chromatography, eluting with hexanes-ethyl acetate (50:50) to give 2.5 g of 4-(3-chloro-phenyl)-2-(5-formyl-2-nitro-phenylamino)-thiazole-5-carboxylic acid amide (VI.2b).

1. temperatureThe mixture was cooled
2. concentrationconcentrated under reduced pressure
3. washwashed once with 100 mL of saturated sodium bicarbonate solution, once with 50 mL of brine
4. dry with materialdried over anhydrous sodium sulfate
5. filtrationThe mixture was filtered
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified by silica gel chromatography
8. washeluting with hexanes-ethyl acetate (50:50)