Water → HCID 14128069, compound

Participants

Reaction Steps

A portion (4.3 g) of the 4-chloro-7,8-dihydro-3-(2-fluorophenyl)furo[2,3-g]-1,2-benzisoxazole-7-methanol obtained in Example 22 was dissolved in 120 ml of acetone. To the solution, a mixture of chromium (VI) oxide (6.5 g), water (15 ml) and concentrated sulfuric acid (9.3 g) was added dropwise under stirring. The stirring was continued at room temperature for 2 hours, then the mixture was left to stand overnight. The insolubles were filtered off by suction, and the solvent was distilled off. Water was added to the residue, followed by extraction with ether. The ether layer was washed with water and dried, and the solvent was distilled off. The residue was recrystallized from acetone/water to yield 2.7 g of 4-chloro-7,8-dihydro-3-(2-fluorophenyl)furo[2,3-g]-1,2-benzisoxazole-7-carboxylic acid. m.p. 191°-193° C.

Provenance & Evidence