反应详情

To a suspension of 2-(4-(tert-butoxycarbonyl)piperazin-1-yl)pyrimidine-5-carboxylic acid (13.8 g, 44.8 mmol), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (12.8 g, 67.2 mmol) and hydroxybenzotriazole (7.2 g, 53.7 mmol) in dichloromethane (200 mL) was added triethylamine (25 mL, 179.2 mmol). The mixture was stirred at room temperature for 1 hour, and then N,O-dimethylhydroxylamine (5 g, 53.7 mmol) was added. The reaction mixture was stirred for another 3 hours. LCMS showed the reaction was completed. The reaction mixture was directly washed with water (100 mL), and the organic layer was dried over sodium sulfate, filtered and concentrated. The residue was purified by silica gel chromatography (petroleum ether:ethyl acetate=1:1) to give tert-butyl 4-(5-(methoxy(methyl)carbamoyl)pyrimidin-2-yl)piperazine-1-carboxylate (11.2 g, 67%) as a white solid. MS (ES+) C16H25N5O4 requires: 351, found: 296 [M-56+H]+.

1. stirringThe reaction mixture was stirred for another 3 hours
2. washThe reaction mixture was directly washed with water (100 mL)
3. dry with materialthe organic layer was dried over sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated
6. customThe residue was purified by silica gel chromatography (petroleum ether:ethyl acetate=1:1)