反应详情

To a suspension of hydrazinecarbothioamide (15.0 g, 165 mmol) in pyridine (100 mL) was added dropwise ethyl 3-chloro-3-oxopropanoate (24.8 g, 165 mmol) over 30 min at 0° C., and the reaction solution was stirred at room temperature for 2 days. The reaction mixture was concentrated under reduced pressure, and methanol was added to the residue. The resulting solid was filtered off, the filtrate was concentrated under reduced pressure, and the residue was extracted with ethyl acetate, THF and saturated aqueous ammonium chloride solution. The organic layer was washed with saturated aqueous ammonium chloride solution, dried over sodium sulfate, and concentrated. The residue was crystallized from ethyl acetate and isopropyl ether, and the obtained crystals were washed with isopropyl ether, and dried to give the title compound (14.2 g, 42%).

1. concentrationThe reaction mixture was concentrated under reduced pressure, and methanol
2. additionwas added to the residue
3. filtrationThe resulting solid was filtered off
4. concentrationthe filtrate was concentrated under reduced pressure
5. extractionthe residue was extracted with ethyl acetate, THF and saturated aqueous ammonium chloride solution
6. washThe organic layer was washed with saturated aqueous ammonium chloride solution
7. dry with materialdried over sodium sulfate
8. concentrationconcentrated
9. customThe residue was crystallized from ethyl acetate and isopropyl ether
10. washthe obtained crystals were washed with isopropyl ether
11. customdried