Methyl chloroformate → Flometoquin

Participants

Reaction Conditions

Reaction Steps

Dimethylformamide (980 ml) and 98 g of 2-ethyl-3,7-dimethyl-6-(4-(trifluoromethoxy)phenoxy)quinolin-4(1H)-one were charged into a 2000-ml glass flask equipped with a stirring device, a thermometer, a reflux condenser, and a calcium chloride tube under a nitrogen atmosphere, and the temperature of the contents of the flask was cooled to 15° C. A 55% sodium hydride (18.2 g) was added thereto, and a reaction was allowed to proceed at 15 to 20° C. for one hr. Methyl chloroformate (32.1 g) was added dropwise into the reaction solution, and a reaction was allowed to proceed at room temperature for one hr. The reaction mixture was poured into 5 L of ice-water contained in the a 10-L plastic container, and the mixture was stirred at room temperature for two hr. The precipitated solid was collected by filtration through a suction filter and was washed with water and n-hexane. The solid was dried under the reduced pressure to give 2-ethyl-3,7-dimethyl-6-(4-(trifluoromethoxy)phenoxy)quinolin-4-yl methyl carbonate (103.3 g, yield: 91.4%). The results of 1H-NMR analysis showed that the compound thus obtained was No. 120 described in a brochure of International Publication No. 2006/013896.

Provenance & Evidence