Trimethyl orthoformate → Methyl (E)-4-Chloro-3-methoxy-2-butenoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

31.0 g (0.2 mol) of 4-chloroacetoacetic acid methyl ester is mixed with 106.0 g (1.0 mol) of orthoformic acid trimethyl ester. 30.0 g of Amberlyst-15 ion exchange resin is added under argon with stirring. Under vigorous formation of gas, the reaction temperature rises to 40° C. After 5 hours of stirring, no educt can any longer be detected in thin-layer chromatography. It is filtered from the ion exchange resin and the residue is distilled in a water jet vacuum. The distillate is mixed with 1.0 g of p-toluene sulfonic acid monohydrate and slowly heated to 150° C., and methanol is distilled off. The reaction mass is then distilled in a water jet vacuum. 24.7 g of a colorless liquid with a boiling point bp12 =93° C. is obtained. Further data concerning the compound is:

Herkunft & Nachweise