Nitric Acid → methyl 2-chloro-3-[5-fluoro-2-nitro-4-(1-methyl-6-trifluoromethyl-2,4(1H,3H)-pyrimidinedion-3-yl)phenyl]propanoate

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Reaction Conditions

Reaction Steps

A mixture of 10.4 grams (0.025 mole) of methyl 2-chloro-3-[3-fluoro-4-(1-methyl-6-trifluoromethyl-2,4(1H,3H)-pyrimidinedion-3-yl)phenyl]propanoate in 100 mL of concentrated sulfuric acid was stirred for two hours until the methyl propanoate was completely dissolved. The mixture was then cooled to 10° C., and 2.7 grams (0.030 mole) of 70% nitric acid was added dropwise while the temperature of the reaction mixture was held at 10° C. Upon completion of addition, the reaction mixture was allowed to warm to ambient temperature, where it was stirred for one hour. The reaction mixture was then poured into ice-water and stirred until the ice melted. The mixture was extracted with diethyl ether. The extract was washed with water and dried with magnesium sulfate. The mixture was filtered, and the filtrate was concentrated under reduced pressure to a residue. The residue was subjected to column chromatography on silica gel. Elution was accomplished using methylene chloride. The product-containing fractions were combined and concentrated under reduced pressure, yielding 3.2 grams of methyl 2-chloro-3-[5-fluoro-2-nitro-4-(1-methyl-6-trifluoromethyl-2,4(1H,3H)-pyrimidinedion-3-yl)phenyl]propanoate, mp 60°-65° C. The NMR spectrum was consistent with the proposed structure.

Provenance & Evidence