反应详情

温度

23 °C

A solution of 1.0 g (6.3 mmol) 4-chloro-3-methoxyphenol and 5.4 g (6.3 mmol) crotonic acid in 15 ml methane sulfonic acid was heated at 95° C. under nitrogen for 20 hours. The reaction was cooled to 23° C., poured onto 150 ml ice and water and extracted with 100 ml ethyl acetate. The ethyl acetate extract was successively washed with 100 ml water, 2×100 ml 1N sodium hydroxide and 100 ml brine, dried over magnesium sulfate and concentrated in vacuo to a purple crystalline solid. This was purified by flash chromatography on 150 cc silica gel using chloroform as eluant to give the product as a yellow crystalline solid, 1.1 g (78%); m.p. 96°-100° C.

1. extractionextracted with 100 ml ethyl acetate
2. extractionThe ethyl acetate extract
3. washwas successively washed with 100 ml water, 2×100 ml 1N sodium hydroxide and 100 ml brine
4. dry with materialdried over magnesium sulfate
5. concentrationconcentrated in vacuo to a purple crystalline solid
6. customThis was purified by flash chromatography on 150 cc silica gel