反应 #481600

反应方程式

3,4,5-trimethoxy benzaldehyde

sulphuric acid

→

3,5-Dimethoxy-4-hydroxy benzaldehyde

反应条件

后处理

1. 1
   其他at 40° C.
2. 2
   其他for 8 hours

实验过程

Monodemethylation of 3,4,5-trimethoxy benzaldehyde using sulphuric acid at 40° C. for 8 hours yields 3,5-Dimethoxy-4-hydroxy benzaldehyde (Syringaldehyde). Condensation of syringaldehyde with ethyl cyanoacetate in the presence of piperidine—acetic acid and benzene as the reaction medium at reflux temperature under continuous azeotropic water removal yields the title product. The reaction takes about 1.5 hours for completion. The yield obtained is typically 95%.

来源