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

Participants

Reaction Conditions

Reaction Steps

A mixture of methyl 4-chloroacetoacetate (96.5 g) and trimethyl orthoformate (340.2 g) was stirred under argon with 96.5 g of Amberlyst-15 ion exchange resin. The temperature was raised to 40° C. and stirring continued for 5 hours. The resin was filtered off and the filtrate distilled under vacuum (15 mm). The distillate was mixed with 3.2 g of p-toluenesulfonic acid and heated at 150° C. until no more methanol distilled off. Distillation of the residue under vacuum gave 4-chloro-3-methoxy-2-E-butenoic acid, methyl ester, b.p. 75° C. (3 mm Hg).

Provenance & Evidence