反应详情

3-amino-6-(4-isopropylsulfonylphenyl)pyrazine-2-carbohydrazide (2 g, 5.963 mmol) and Et3N (1.810 g, 2.493 mL, 17.89 mmol) were dissolved in THF (128.0 mL) and treated dropwise with ethyl 2-chloro-2-oxo-acetate (814.2 mg, 666.3 μL, 5.963 mmol) at 0° C. The reaction mixture was warmed slowly to room temperature and stirred for 1.5 h. The reaction mixture was filtered and grey solid washed with THF. The filtrate was evaporated to dryness azeotroping with acetonitrile. Then residue was then triturated with acetonitrile to give the product as a yellow solid (1.52 g, 58%); 1H NMR (400 MHZ, DMSO) d 1.19 (m, 6H), 1.32 (m, 3H), 3.34 (m, 1H), 4.32 (m, 2H), 7.88 (m, 2H), 8.56 (m, 2H), 9.07 (s, 1H), 10.95 (s, 1H) and 11.05 (s, 1H) ppm; MS (ES+) 436.32

1. filtrationThe reaction mixture was filtered
2. washgrey solid washed with THF
3. customThe filtrate was evaporated to dryness
4. customazeotroping with acetonitrile
5. customThen residue was then triturated with acetonitrile