Carbon Dioxide → 4-[5-(3,5-Dichloro-phenyl)-2-methyl-5-trifluoromethyl-2,5-dihydro-isoxazol-3-yl]-2-methyl-benzoic acid

Participants

Reaction Conditions

Reaction Steps

210 mg of 3-(4-Bromo-3-methyl-phenyl)-5-(3,5-dichloro-phenyl)-2-methyl-5-trifluoromethyl-2,5-dihydro-isoxazole (IIIa) was dissolved in 20 ml of dry THF, cooled to −90° C. and treated with 0.625 ml BuLi 1.6M in hexane. The mixture was stirred for 1 hour at −80° C. and then a great excess of solid CO2 was added to the mixture. The temperature was allowed to rise up to −30° C. (1 hour) and 5 ml of 1M HCl was added followed with ether. The organic layer was dried and evaporated to dryness. The residual resin was used in the final step without purification.

Provenance & Evidence