| 摘要 |
Tricyclazole (I), a known effective rcie blast controlling agent, was manutd. by reaction of 2-hydrazino- 4 -methyl-benzothiazole (III) with excess HCO2H. I was recovered by adding an aromatic hydrocarbon solvent to the reaction mixt., azeotropically removing excess HCO2H with the solvent, and crystn. and isolation from the solvent. Use of the solvent during work-up improved the yield and purity of I, and reduced the HCO2H consumption by ˜40%. Thus, III on sequential reaction with HCO2H (110-122≦̸C, 16 hrs), removal of HCO2H by distn., addn. of PhMe, distn. of an azeotrope of HCO2H and PhMe, and crystn. gave 86% I (purity=94.7%).
|
