化学合成。
化学合成
合成路线 1(1. 合成:15878-00-9)
产率:74%
合成条件:With oxone; sodium chloride In water at 20℃; for 2.50 h;
实验步骤:通用方法:1-苄基-4-氯-3,5-二甲基-1H-吡唑。向含有1-苄基-3,5-二甲基-1H-吡唑(196mg,1.05mmol)和磁力搅拌棒的16mL小瓶中加入0.7mL水和0.3mL乙酸乙酯。然后,加入NaCl(123mg,2mmol),将小瓶置于室温水浴中以控制放热。最后,加入Oxone(322mg,0.52mmol或1.05mmol KHSO 5)并盖上小瓶。在连续剧烈搅拌下进行反应,直至TLC(1小时)所示没有剩余原料残留。剩余的氧化剂用固体亚硫酸氢钠还原,直到淀粉碘化物纸测试为阴性。加入水(5mL),用1:1己烷/乙醚(3×5mL)萃取混合物。将合并的有机部分干燥(MgSO 4)并浓缩,得到粗产物,将其通过快速色谱(14×1cm),9:1己烷/乙酸乙酯洗脱液纯化。得到纯的1-苄基-4-氯-3,5-二甲基-1H-吡唑,为浅黄色油状物(215mg,收率93%)。
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