Triethylamine → Methyl 4-[5-(3,5-dichlorophenyl)-4,5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-1-naphthalenecarboxylate

Participants

Reaction Steps

To a stirred solution of methyl 4-[(hydroxyimino)methyl]-1-naphthalenecarboxylate (i.e. the product from Step A) (1.0 g, 4.36 mmol) in N,N-dimethylformamide (5.0 mL) was added N-chlorosuccinimide (1.16 g, 8.72 mmol). This mixture was stirred for 1.5 h at room temperature, and then a solution of 1,3-dichloro-5-[1-(trifluoromethyl)ethenyl]benzene (i.e. the product from Step B) (3.20 g, 13.1 mmol) and triethylamine (6.1 mL, 43.6 mmol) in N,N-dimethylformamide (4.0 mL) was added. After stirring for additional 2 h at room temperature, the reaction mixture was diluted with water and extracted with ethyl acetate. The organic layer was washed with brine, dried (Na2SO4), and concentrated under reduced pressure. The residue was purified by silica gel chromatography using hexanes/ethyl acetate as eluent to afford the title compound as a pale yellow oil (700 mg, 34% yield).

Provenance & Evidence