2,5-二甲氧基苯乙胺盐酸盐合成新工艺

New synthetic method of 2,5-dimethoxyphenethy- lamine hydrochloride

目的寻找合成 2 ,5 二甲氧基苯乙胺新方法。方法以 2 ,5 二甲氧基苯甲醛与硝基甲烷 (兼溶剂 )在少量乙酸铵存在下 ,85℃保温 30min ,合成 2 ,5 二甲氧基 β 硝基苯乙烯 (Ⅰ ) ,收率 90 % ;将(Ⅰ )加到乙醇水盐酸溶液中 ,在 70～ 85℃ ,加入锌粉和少量汞 ,还原得 2 ,5 二甲氧基苯乙胺 (Ⅱ ) ,加盐酸甲醇溶液成盐 ,收率达到 6 0 %。结果使用锌粉和少量汞代替LiAlH4 或锌汞齐作还原剂可以还原 2 ,5 二甲氧基 β 硝基苯乙烯制备 2 ,5 二甲氧基苯乙胺。 结论该合成方法工艺简单 ,还原剂便宜。

Objective To find a new synthetic method of 2,5 dimethoxyphenethylamine. Methods The 2,5 dimethoxybenzaldehyde was mixed with MeNO 2 (as solution) and NH 4OAc ,the mixture was heated to 85℃ and kept for 30 min to form 2,5 dimethoxy β nitro styrene (Ⅰ); yield 90%; (Ⅰ) was added to the mixture of water, alcohol and hydrochloric acid, after heating to 65～70℃, the power Zn and a little amount of Hg were added to synthesize 2,5 dimethoxyphenethylamineo(Ⅱ) was added to the solution of hydrochloric acid and methanol to form 2,5 dimethoxyphenethylamine hydrochloride in yield 60%. Results Using the power Zn and a little amount of Hg as a reducing agent instead of LiAlH 4 or alloy of Zn and Hg to reduce 2,5 dimethoxy β nitro styrene to 2,5 dimethoxyphenethylamine. Conclusions This method is simple and the reducer is cheap.