Chlorodifluoromethane → 4-(Difluoromethoxy)-6-methylpyrimidin-2-amine

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Reaction Steps

Gaseous difluorochloromethane is introduced, over a period of 12 hours at a temperature of 70° to 75° C., into a solution of 62.5 g of 2-amino-4-hydroxy-6-methyl-pyrimidine in 500 ml of water, 100 ml of 40% sodium hydroxide solution and 100 ml of dioxane. There are added during this time, in each case at intervals of 1 hour and in equal portions, a total of 160 g of solid sodium hydroxide. The organic phase is separated, and concentrated to about 1/10 of its volume; the residue is poured into water, and the solid substance which has precipitated is removed. The yield is 39.9 g of 2-amino-4-difluoromethoxy-6-methyl-pyrimidine, m.p. 136° to 137° C. (compound No. 1.1).

Provenance & Evidence