反应详情

A mixture of 4,6-dimethyl-7-hydroxycoumarin (III) (5.0 g), anhydrous K2CO3 (10 g), chloroacetone (2.5 ml) and acetone (150 ml) was refluxed for 12 h under stirring. From the refluxed mixture the solid was filtered and washed several times with acetone. The acetonic solution and the pooled washings were concentrated to dryness and the residue crystallized from MeOH, yielding 4,6-dimethyl-7-acetonyloxycoumarin (XXXVII) (5.1 g; m.p. 190° C.) ##STR42##

1. temperaturewas refluxed for 12 h
2. filtrationFrom the refluxed mixture the solid was filtered
3. washwashed several times with acetone
4. concentrationThe acetonic solution and the pooled washings were concentrated to dryness
5. customthe residue crystallized from MeOH