Methyl Isocyanate → 2-chloro-5-[3,6-dihydro-2,6-dioxo-3-methyl-4-trifluoromethyl-1(2H)-pyrimidinyl]-4-fluorophenyl methylcarbamate

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Reaction Steps

0.51 g of methyl isocyanate and subsequently one drop of triethylamine are added at room temperature while stirring to a solution of 2.00 g of 3-(4-chloro-2-fluoro-5-hydroxyphenyl)-1-methyl-6-trifluoromethyl-2,4(1H,3H)-pyrimidinedione in 20 ml of methylene chloride. The reaction mixture is stirred for one hour and evaporated to dryness under reduced pressure. The residue is purified by chromatography on a silica gel column using diethyl ether-n-hexane (2:1) as the eluent. There is obtained 2-chloro-5-[3,6-dihydro-2,6-dioxo-3-methyl-4-trifluoromethyl-1(2H)-pyrimidinyl]-4-fluorophenyl methylcarbamate, 1H-NMR (CDCl3, 400 MHz): 7.33 ppm (d,1H), 7.24 ppm (d,1H), 6.34 ppm (s,1H), 5.21 ppm (q,1H), 3.54 ppm (d,3H), 2.88 ppm (d,3H).

Provenance & Evidence