反应详情

A mixture of 3-chloro-6-aminopyridazine [J. Druey et al., Helv. Chim. Acta., 37, 121 (1954)] (8.20 g, 63.56 m mol) and ethyl ethoxymethylenemalonate (15.0 g, 69.4 m mol) in diphenyl ether (70 ml) was heated to distil out ethanol produced. After cooling, the mixture was diluted with n-hexane (300 ml) to precipitate the crude title product, which was dissolved in chloroform (200 ml), treated with a small amount of carbon and evaporated under reduced pressure to 50 ml. The residual solution was diluted with n-hexane (200 ml) to precipitate pure title product. Yield, 7.73 g (56%), M.p. 149°-152° C.

1. temperaturewas heated
2. customto distil out ethanol
3. customproduced
4. temperatureAfter cooling
5. customto precipitate the crude title product, which
6. dissolutionwas dissolved in chloroform (200 ml)
7. additiontreated with a small amount of carbon
8. customevaporated under reduced pressure to 50 ml
9. additionThe residual solution was diluted with n-hexane (200 ml)
10. customto precipitate pure title product
11. customYield