Triethylamine → 4-[5-(3,5-Dichloro-4-cyano-phenyl)-5-trifluoromethyl-4,5-dihydro-isoxazol-3-yl]-2-methyl-benzoic acid tert-butyl ester

Participants

Reaction Steps

To a solution of 4-(hydroxyimino-methyl)-2-methyl-benzoic acid tert-butyl ester (1.47 g) in N, N-dimethylformamide (13 ml) was added N-chlorosuccinimide (“NCS”) (832 mg). The reaction mixture was stirred at ambient temperature for 2 hours. More N-chlorosuccinimide (“NCS”) (850 mg) was added and the reaction mixture was stirred at ambient temperature for 1 hour. A solution of 2,6-Dichloro-4-(1-trifluoromethyl-vinyl)-benzonitrile (1.37 g) and triethylamine (0.72 ml) in N,N-dimethylformamide (13 ml) was added dropwise to the reaction mixture. The reaction mixture was stirred at ambient temperature for 17 hours. Water and ethyl acetate were added and the phases were separated. The organic layer was washed with water, dried over sodium sulfate and concentrated. The residue was purified by chromatography on silica gel to give 4-[5-(3,5-Dichloro-4-cyano-phenyl)-5-trifluoromethyl-4,5-dihydro-isoxazol-3-yl]-2-methyl-benzoic acid tert-butyl ester (0.902 g). 19F-NMR (CDCl3, 75 MHz): −78.93 ppm.

Provenance & Evidence