反应详情

To a solution of 5-amino-3-(2-chlorophenyl)pyrazole (3.8 g, 19.6 mmol) in THF (150 mL) was added dropwise benzoyl isothiocyanate (2.9 mL, 21.56 mmol). The reaction mixture was stirred at room temperature for 4 hours, then 4 N aqueous solution of NaOH (8 mL) was added, and the reaction mixture was further stirred at room temperature for 17 hours. The reaction mixture was neutralized to pH 7 with 1 N aqueous HCl, and extracted with EtOAc (3×). The combined organic layers were directly purified on silica gel with 0-10% MeOH in CH2Cl2 as eluent to provide 3.47 g (72 % yield) of [5-(2-chloro-phenyl)-2H-pyrazol-3-yl]-thiourea as a tan solid.

1. stirringthe reaction mixture was further stirred at room temperature for 17 hours
2. extractionextracted with EtOAc (3×)
3. customThe combined organic layers were directly purified on silica gel with 0-10% MeOH in CH2Cl2 as eluent