Acetic Anhydride → methyl 3-acetamidothiophene-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

With simultaneous heating in an oil bath, 567 ml of acetic anhydride are added dropwise to a mixture of 942 g of methyl 3-aminothiophene-2-carboxylate and 1 000 ml of toluene, and the mixture is then boiled under reflux conditions for 1½ hours and subsequently cooled in an ice bath to about 0° C. The crystals are filtered off and washed twice with a little isopropanol and twice with diisopropyl ether. Methyl 3-acetylaminothiophene-2-carboxylate can be obtained from the filtrate by further concentration and crystallization. M.p. 93-95° C.

Provenance & Evidence