反应详情

2.0 g (0.126 mole) of 3-diazo-oxindole is taken up in xylene (85 ml), treated with 1.2 equivalents of n-butyl propiolate (1.9 g) and refluxed under a stream of nitrogen for 17 hours in an oil bath. The light coral-colored precipitates that form are cooled and filtered off and washed with ether. Yield: 3.0 g, m.p. 190°-195°; 83.57% crude yield. The crude product is taken up in boiling absolute ethanol (250 ml), treated with activated carbon, filtered and concentrated down on a steam bath to a volume of ~75 ml. After cooling, tan-colored precipitates are filtered off and dried in a vacuum oven at room temperature for 4 hours. Yield: 2.2 g, m.p. 198°-200°.

1. temperaturerefluxed under a stream of nitrogen for 17 hours in an oil bath
2. customThe light coral-colored precipitates that form
3. temperatureare cooled
4. filtrationfiltered off
5. washwashed with ether
6. additiontreated with activated carbon
7. filtrationfiltered
8. concentrationconcentrated down on a steam bath to a volume of ~75 ml
9. temperatureAfter cooling
10. customtan-colored precipitates
11. filtrationare filtered off
12. customdried in a vacuum oven at room temperature for 4 hours