Nitroethane → HCID 54125846, compound

Participants

Reaction Steps

Triethylamine (0.050 mL, 0.36 mmol) was added in portions to a mixture of 2-bromo-1-methoxy-4-(2-methoxyvinyl)benzene (500 mg, 2.06 mmol, 1:1 ratio of E- and Z-isomers), phenylisocyanate (0.489 mL, 4.5 mmol), and nitroethane (0.180 mL, 2.5 mmol) in dry toluene (2.0 mL) at room temperature. After stirring at room temperature for 5 h followed by 1 h at 100° C. for 1 h, the mixture was allowed to stand overnight at room temperature. Water (6 mL) was then added and stirring was continued at room temperature for 4 h. The mixture was filtered, the layers of the filtrate were separated, and the aqueous layer was extracted with 2×30 mL of toluene. The combined organic layers were dried over sodium sulfate and evaporated. Flash column chromatography on 50 g of silica gel eluting with 2 L of 10% of ethyl acetate/hexane yielded 4-(3-bromo-4-methoxyphenyl)-5-methoxy-3-methyl-4,5-dihydroisoxazole as 0.28 g of yellow oil containing some remaining impurity. 1H NMR (400 MHz, CDCl3): δ 7.33 (d, 1H, J=2 Hz), 7.03(dd, 1H, J=9, 2 Hz), 6.87 (d, 1H, J=9 Hz), 5.15 (d, 1H, J=1 Hz), 3.89 (s, 3H), 3.88 (s, 1H), 3.47 (s, 3H), 1.83 (s, 3H). Mass spectrum (NH3CI): m/e=300 (M+1).

Provenance & Evidence