反应详情

To a mixture of sodium ethoxide (100 ml; prepared from 1.38 g sodium and 100 ml ethanol) and 2-hydroxy-1-acetonaphthone (11.29 g, 0.06 mol) was added ethyl cyanoacetate (11.1 ml, 0.1 mol). The resulting mixture was stirred at reflux temperature for 2 h. The reaction mixture was cooled in a ice bath and the precipitate was filtered off and washed with water (20 ml) and cold ethanol (3×20 ml), dried in vacuo at 50° C. for 18 h which afforded (9 g) of crude product. The crude product (9 g) was recrystallised from a mixture of acetone (1 l) and water (25 ml) affording 5.33 g (38%) of 1-methyl-3-oxo-3H-benzo[f]chromene-2-carbonitrile as a solid.

1. temperatureat reflux temperature for 2 h
2. temperatureThe reaction mixture was cooled in a ice bath
3. filtrationthe precipitate was filtered off
4. washwashed with water (20 ml) and cold ethanol (3×20 ml)
5. customdried in vacuo at 50° C. for 18 h which
6. customafforded (9 g) of crude product
7. customThe crude product (9 g) was recrystallised from a mixture of acetone (1 l) and water (25 ml)