Ammonium Chloride → {4-[5-(3,5-Dichloro-phenyl)-5-trifluoromethyl-4,5-dihydro-isoxazol-3-yl]-2-methyl-phenyl}-oxo-acetic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-(4-bromo-3-methyl-phenyl)-5-(3,5-dichloro-phenyl)-5-trifluoromethyl-4,5-dihydro-isoxazole (1.00 g) in THF (40 mL) was added tert-butyllithium (16.2 mL of a 1.6 M solution in pentane) at −78° C. After 10 min at this temperature, MgBr2 (0.15 M in THF, 10.3 mL) was added dropwise and left for another 15 min. Oxalic acid methylester chloride (284 mg) was added and the mixture was stirred at −78° C. for 1 h before it was allowed to warm to room temperature over night. Saturated aqueous NH4Cl solution was added and the mixture was extracted with MTBE. The organic layer was separated, dried (Na2SO4) and concentrated in vacuum. The residue was purified by flash chromatography on silica gel to yield the title compound (167 mg, 16%).

Provenance & Evidence