反应详情

To a boiling solution of 4.2 g. (0.02 m.) of 3,5-diacetyl-4,6-dihydroxy-2H-pyran-2-one in 150 ml. of benzene/methanol is added 1.2 g. (0.02 m.). of n-propylamine and the resulting mixture is refluxed overnight. The reaction mixture is concentrated, filtered and the solid treated with water to give pure 5-acetyl-4-hydroxy-3-[1-(n-propylamino)-ethylidene]-2H-pyran-2,6(3H)-dione, m.p. 145° -148° C.

1. concentrationThe reaction mixture is concentrated
2. filtrationfiltered
3. additionthe solid treated with water