Sodium Hydroxide → 6-(4,6-Dimethoxypyrimidin-2-yl)oxy-3-methyl-benzisoxazol-7-carboxylic Acid

Participants

Reaction Conditions

Reaction Steps

While heating and stirring 1.0 g of methyl 6-(4,6-dimethoxypyrimidin-2-yl)oxy-3-methylbenzisoxazol-7-carboxylate in 20 ml of N,N-dimethylsulfoxide at 70° C., 1.7 ml of a 2N sodium hydroxide aqueous solution was dropwise added thereto over a period of 10 minutes. Then, the mixture was further heated and stirred at 70° C. for 30 minutes. The mixture was returned to room temperature, then poured into water and extracted with diethyl ether. The aqueous layer was acidified with 10% hydrochloric acid, and precipitated crystals were extracted with ethyl acetate. The organic layer was washed with water and then dried over anhydrous sodium sulfate. It was then concentrated under reduced pressure, and the crystals thereby obtained were washed with isopropyl ether to obtain 0.7 g (yield: 71%) of the desired compound.

Provenance & Evidence