反应详情

A solution of 2,4-dihydroxytoluene (10.0 g) in ethylacetoacetate (12 ml) was poured in small portion into conc. H2SO4 (26 ml), chilling in an ice bath. After the addition was completed the solid obtained was separated by filtration, washed several times with water up to neutrality of the washings, dried and crystallized from MeOH, yielding 4,6-dimethyl-7-hydroxycoumarin (III) (10.64 g; m.p. 273° C.). ##STR8##

1. temperaturechilling in an ice bath
2. additionAfter the addition
3. customobtained
4. customwas separated by filtration
5. washwashed several times with water up to neutrality of the washings
6. customdried
7. customcrystallized from MeOH