反応 #481600

反応方程式

3,4,5-trimethoxy benzaldehyde

sulphuric acid

→

3,5-Dimethoxy-4-hydroxy benzaldehyde

反応条件

後処理

1. 1
   その他at 40° C.
2. 2
   その他for 8 hours

実験手順

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%.

出典