反应详情

To a solution of 3-aminopyrazole (500 mg, 6 mmol), in anh. DMF (10 mL), at r.t., under N2, was added 3-chloropropyl isocyanate (1.2 mL, 2 eq) and the reaction was stirred for 24 hr. The reaction was not complete and more isocyanate (1.2 mL, 2 eq) was added. The reaction mixture was stirred for an additional 48 hr. It was then poured into CH2Cl2/sat.aq. NaCl and the phases were separated. The aqueous layer was extracted with CH2Cl2 (2×20 mL) and the combined organic extracts were dried over anh. Na2SO4. The solids were filtered and the solvent evaporated. The crude product was purified by flash chromatography (Biotage 40, cHex/EtOAc 7:3) to give the title compound as a white solid (620 mg, 32%).

1. stirringThe reaction mixture was stirred for an additional 48 hr
2. customNaCl and the phases were separated
3. extractionThe aqueous layer was extracted with CH2Cl2 (2×20 mL)
4. dry with materialthe combined organic extracts were dried over anh. Na2SO4
5. filtrationThe solids were filtered
6. customthe solvent evaporated
7. customThe crude product was purified by flash chromatography (Biotage 40, cHex/EtOAc 7:3)