Sulfuric Acid → 2-[3-(4-Chlorobenzoyl)isoxazol-5-yl]propionic acid

Participants

Reaction Steps

To a mixture of 11.0 g of 2-[3-(4-chlorobenzoyl)-isoxazol-5-yl]propan-1-ol in 1000 ml of CH2Cl2, a few crystals of tetra-n-butylammonium hydrogen sulfate and 150 ml of 9M H2SO4 was added 12.3 g of pulverized K2Cr2O7. The resulting mixture was stirred at room temperature for 1.5 hour. After allowing the mixture to settle, it was decanted from the unreacted dichromate. The aqueous phase was separated and the organics were washed with water and brine, and dried over MgSO4. Concentration of the product gave 8.0 g of a solid. Recrystallization from toluene with norite for decolorizing gave 2.0 g of a solid, m.p. 119°-123°. A second recrystallization from toluene gave 1.6 g (13%) of a solid, m.p. 122.5°-124.5°.

Provenance & Evidence