负载型蒙脱土催化芦竹碱的微波合成

Catalytic Synthesis of Gramine by Immobilized Montmorillonite under Microwave Irradiation

以吲哚(1)、甲醛(2)和二甲胺(3)为原料,固载蒙脱土(MMT)/路易斯酸(L)为催化剂,通过微波辐射合成了芦竹碱(4),其结构经1H NMR确证。考察了MMT/L、反应温度、反应时间、溶剂和物料比r[n(1)∶n(2)∶n(3)]对4产率的影响。结果表明:在最优反应条件[甲醇为溶剂,MMT/Zn Cl2为催化剂,MMT/Zn Cl218 mg,1 1mmol,r=1.0∶1.3∶1.3,于50℃反应10 min]下合成4,产率93.8%。MMT/Zn Cl2循环使用3次,4产率60.0%

Gramine（ 4） was synthesized by microwave-assist method from indole（ 1）,formaldehyde（ 2） and dimethylamine（ 3）,using immobilized montmorillonite /Lewis acid as the catalyst. The structure was confirmed by1 H NMR. The effects of catalyst,reaction temperature,reaction time,solvent and molar ratio{ r[n（ 1） ∶ n（ 2） ∶ n（ 3） ]} on the yield of 4 were investigated. The optimum conditions of synthesis 4 at 50 ℃ for 10 min were as follows： methanol as the solvent,MMT / Zn Cl2 as the catalyst,MMT / Zn Cl20. 15 mmol,1 1 mmol,r = 1. 0 ∶ 1. 3 ∶ 1. 3. The yield of 4 was 93. 8% under the optimum conditions. The yield of 4 was 60. 0% after MMT / Zn Cl2 used for three times.