吡唑并[1,5-a]吡啶-5-羧酸的合成改进

Improved synthesis of pyrazolo[1,5-a]pyridine-5-carboxylic acid

以4-吡啶甲酸为原料,经过还原反应、羟基的保护、氮的氨基化、1,3-偶极体环加成反应,脱羧反应和高锰酸钾的氧化反应,最终得到目标产物吡唑并[1,5-a]吡啶-5-羧酸。该合成方法原料价格便宜,操作简单,对设备复杂性要求低,反应所需溶剂毒性小,工艺路线缩短。

4-Pyridine carboxylic acid was chosen as raw material. By the following procedures： reduction reaction,hydroxyl group protection,N-amination,1,3-dipolar cycloaddition,the decarboxylation reaction and the oxidation reaction of potassium permanganate,and get the resulting product pyrazolo[1,5-a]pyridine-5-carboxylic acid. This synthetic method has many advantages including： the cheap raw material,the easy operation,low requirements of the complexity of the equipments,low toxicity of the solvents,the shorter routes.