反应详情

A solution of hex-1-ynylbenzene (0.274 mL, 1.56 mmol), dimethyl 2-nitromalonate (0.421 mL, 3.12 mmol), 1-butyl-3-methylimidazoliumhexafluorophosphate (0.032 mL, 0.156 mmol) in toluene (6 mL) was subjected to the microwave at 170° C. for 150 min. The reaction mixture was concentrated under reduced pressure, and the residue was purified by flash silica gel chromatography using 5% ethyl acetate in hexane to give methyl 4-butyl-5-phenylisoxazole-3-carboxylate (0.142 g, 0.531 mmol, 34.1% yield) as a clear, colorless oil. The product was 97% pure by HPLC with a ret. time=3.11 min.−Column. CHROMOLITH® SpeedROD 4.6×50 mm (4 min.); Solvent A=10% MeOH, 90% H2O, 0.1% TFA; Solvent B=90% MeOH, 10% H2O, 0.1% TFA. LC/MS M+1=260.2.

1. concentrationThe reaction mixture was concentrated under reduced pressure
2. customthe residue was purified by flash silica gel chromatography