钠氢多加一些

钠氢与DMF体系，加入吡唑后适当控温。反应应该放热，后期稍微升温至室温-60℃之间。反应完毕后保温。
并保持一定的温度下滴加溴代烷，加入1%的KI作为催化剂。保持一定温度反应。
该反应的温度控制比较重要，其次是水份控制。

To the suspension of sodium hydride (1.10 eq.) in tetrahydrofurane (0.20 mL/rnmol) wasadded the solution of pyrazole (1.0 eq.) in tetrahydrofurane (0.12 mL/mmol) dropwise,while the temperature was kept under 20 °C. After the mixture was stirred at room temperature for 30 minutes, the appropriate halide (1.20 eq.) was added and the mixture was stirred further at same temperature for 16 hours. Next, the reaction mixture was refluxed for 15 hours. After completion the resulting precipitate was filtered off; the filtratewas concentrated then the residue was poured onto a mixture of water and ethyl acetate. The phases were separated, and the aqueous layer was extracted with ethyl acetate. The combined organic layers were dried over Na2SO4, filtered and concentrated under reduced pressure. The crude product was purified via distillation. Using 2-bromopropanc in General Procedure 9G 1-isopropylpyrazole was obtained，

1）原料溶于THF，降温至0度以下，控制温度分批加入NaH（NaH含量一般是60%，请注意当量）,加完NaH搅拌半小时，再加溴代异戊烷，升温至室温反应。
2）我们之前也有碰到低温不反应的，将原料溶于THF，升温至回流，分批加入NaH，加完NaH搅拌半小时，再加溴代异戊烷。