Reaktion #481601

Reaktionsgleichung

3,4,5-trimethoxybenzaldehyde

sulphuric acid

→

syringaldehyde

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeat 40° C.
2. 2
   Sonstigefor 8 hours

Vorschrift

Monodemethylation of 3,4,5-trimethoxybenzaldehyde using sulphuric acid at 40° C. for 8 hours as described above in Example 1 yields syringaldehyde. Condensation of 3,5-Dimethoxy-4-hydroxy benzaldehyde (Syringaldehyde) with diethyl malonate 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 7.5 hours for completion.

Quelle