4-苄氧基-1H-吲唑的合成新方法

A New Synthesis Route of 4-(Benzyloxy)-1H-Indazole

以2-甲基-3-硝基苯酚(I)为原料,先后经过加氢还原、乙酰化、亲核取代、关环及胺解反应,合成了4-苄氧基-1H-吲唑(VI),总的收率为76.3%,所得目标化合物采用FTIR、1H NMR及ESI-MS进行结构表征.研究了4-苄氧基-1-乙酰基-吲唑(Ⅴ)的合成工艺,结果表明,当亚硝酸异戊酯与N-(3-苄氧基-2-甲基苯基)乙酰胺(Ⅳ)的体积比为1.6∶1,反应温度为90℃,反应时间为16 h时,收率可达87.1%.该合成方法具有操作简单、收率高的优势.

4-（benzyloxy）-lH-indazole （VI） is synthesized via five-step reaction： hydrogenation, acetylation, nucle- ophilic substitution, diazotization and aminolysis by using the 2-methyl-3-nitrophenol（ I ） as starting materials. And the total yield is 76.3%. The structure of the aim compound is characterized by FrIR,1H NMR and ESI-MS. In this paper, the synthesis procedure of 1-（4-（benzyloxy）-lH-indazol-l-yl）ethanone （V） is investigated in detail. The re- sults show that the yield is 87.1% when the molar ratio of isoamyl nitrite to N- （3- （benzyloxy）-2- methylphenyl）acetamide（ IV ） is 1.6：1, the reaction temperature is 90 ~C, and the reaction time is 16 h. This synthesis route is easy to handle and has high yield.