Potassium Carbonate → HCID 18916435, compound

Participants

Reaction Steps

Under a nitrogen atmosphere a stirred solution of 1.0 gram (2.5 mmole) of 3-(2-t-butyl-4-chloro-6-fluorobenzoxazol-7-yl)-6-trifluoromethyl-2,4-(1H,3H)pyrimidinedione (prepared in Example 1, Steps A-E), 0.41 gram (3.0 mmole) of potassium carbonate, and 50 mL of tetrahydrofuran was cooled in an ice bath. To this was added 1.1 grams (about 5 mmole) of 1-aminooxysulfonyl-2,4,6-trimethylbenzene. Upon completion of the addition the reaction mixture was stirred in the ice bath for ten minutes, then warmed to ambient temperature, where it stirred for an additional 18 hours. After this time the reaction mixture was poured into 150 mL of aqueous 10% ammonium chloride solution and extracted with two 75 mL portions of diethyl ether. The combined extracts were washed with two 50 mL portions of an aqueous saturated sodium chloride solution. The organic layer was dried with magnesium sulfate and filtered. The filtrate was concentrated under reduced pressure to an oil, which was subjected to column chromatography on silica gel. Elution was accomplished with 6:1 heptane:ethyl acetate. The product-containing fractions were combined and concentrated under reduced pressure, yielding 0.75 gram of 3-(2-t-butyl-4-chloro-6-fluorobenzoxazol-7-yl)-1-amino-6-trifluoromethyl-2,4-(1H,3H)pyrimidinedione, m.p. 90°-92° C. The NMR spectrum was consistent with the proposed structure.

Provenance & Evidence