邻硝基乙苯法合成3-甲基吲哚

Synthesis of 3-Methylindole from o-Nitroethylbenzene

考察了3-甲基吲哚的合成路线。以氯霉素工业大量副产的邻硝基乙苯为原料,经缩合、催化氢化及催化环合三步反应成功合成了3-甲基吲哚,总摩尔收率69.5%。进一步研究表明,缩合反应必须采用强碱性催化剂如甲醇钠催化;铂炭或钯炭均不能有效催化2-(2-硝基苯基)-丙-1-醇的硝基还原反应,而骨架镍催化剂则是该反应的良好催化剂;在环合反应条件下,骨架镍催化剂具有良好的活性和稳定性。该法为3-甲基吲哚的合成提供了一条经济路线。

Starting from o-nitroethylbenzene, a mass-produced byproduct of chloramphenicol industry, through condensation,catalytic hydrogenation and catalytic cyclization,3-methylindole was sucessfully synthesized. The total molar yield was 69.5 %. Further studies showed that, strong bases like sodium methylate should be used as catalysts in the condensation reaction; the nitro reduction of 2-（2- nitrophenyl）-propan-l-ol could not be effectively catalyzed by Pt/C or Pd/C, although this reaction went well with Raney nickel; under the cyclization conditions, the Raney nickel catalyst showed excellent activity and stability. This method provided an economical route for synthesis of 3- methylindole.