反应详情

温度

120 °C

A mixture of 800 mg (4.57 mmol) of 4-methyl-1-tetralone oxime and 4.0 g of polyphosphoric acid was heated at 120° C. in an oil bath for 20 minutes. The dark brown mixture was cooled to 80° C. and poured into ice water. The solution was neutralized by the addition of 10% aqueous sodium carbonate then extracted chloroform (3×50 mL). The combined extracts were washed with water, dried over magnesium sulfate and filtered. Evaporation of the solvent followed by column chromatography on silica gave the product as an off-white solid (670 mg, 84%). 1H NMR (200 MHz, CDCl3): 1.30 (d, 8 Hz, 3H), 1.68 (m, 1H), 2.30 (m, 3H), 3.11 (m, 1H), 6.98 (m, 1H), 7.15-7.30 (m, 3H), 8.55 (br s, 1H). 13C NMR: 18.22, 32.89, 32.98, 37.28, 121.95, 125.67, 125.93, 126.98, 137.69, 137.80, 176.04.

1. temperatureThe dark brown mixture was cooled to 80° C.
2. washThe combined extracts were washed with water
3. dry with materialdried over magnesium sulfate
4. filtrationfiltered
5. customEvaporation of the solvent