Carbon Dioxide → Methyl 1,4-dihydro-7-methoxy-4-oxo-6-quinolinecarboxylate

Participants

Reaction Conditions

Reaction Steps

5-((3-Methoxy-4-methoxycarbonylanilino)methylene)-2,2-dimethyl-1,3-dioxane-4,6-dione (10 g, 29.8 mmol) was suspended in DOWTHERM A, (trade mark of Fluka Chemie AG), (125 ml) and heated to 180-190° C. over 30 minutes. The starting material dissolved at 100° C. and carbon dioxide came off at approximately 180° C. The heating was stopped after a further 30 minutes and the product precipitated out as the temperature dropped. Upon reaching 40° C. ether was added and the mixture was stirred for 30 minutes. The solid was collected by filtration, washed with ether and dried under vacuum to give 7-methoxy-6-methoxycarbonyl-1,4-dihydroquinolin-4-one (5.56 g, 80%).

Provenance & Evidence