Diethyl 2-(ethoxymethylidene)-3-oxobutanedioate → HCID 19958265, compound

Participants

Reaction Steps

5-Amino-3-methylisoxazole (12.25 g, 0.125 mol) and diethyl (ethoxymethylene)oxalacetate (33.55 g, 0.138 mol) are dissolved in 200 mL glacial acetic acid under an N2 atmosphere. The solution is heated to reflux for hours, then stirred at room temperature for 65 hours. The solution is poured into ice water, causing the precipitation of a red solid. The solid is collected by filtration, redissolved in 175 mL glacial acetic acid and reprecipitated with the addition of ice. The resulting yellow sol is collected by filtration and air dried, giving 14.20 g of product, yield 40.8%, having melting point 95°-99° C. A small amount is recrystallized from hexanes/ethyl acetate, melting point 100°-101° C.

Provenance & Evidence