Nitromethane → 1-[3-chloro-4-(2-nitroethenyl)phenyl]-3-(trifluoromethyl)-1H-pyrazole

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-chloro-4-[3-(trifluoromethyl)-1H-pyrazol-1-yl]benzaldehyde (i.e. the product of Step A; 6.0 g, 0.025 mol) in acetic acid (24 mL) was added ammonium acetate (5.6 g, 73 mmol), and the resulting mixture was stirred for 15 min at 0° C. Nitromethane (12.5 g, 204 mmol) was then added, and the mixture was stirred at 80° C. for 2 h. The reaction mixture was poured into ice water and extracted with ethyl acetate (100 mL). The aqueous layer was extracted with ethyl acetate (2×250 mL), and the combined organic layers were washed with brine (200 mL), dried (Na2SO4) and concentrated under reduced pressure. The residue was purified by flash column chromatography on silica gel eluted with 30% ethyl acetate in hexanes to afford the title compound (7.1 g).

Provenance & Evidence