反应详情

27 g of 2-hydroxy-4-isopropyloxy-phenyl-benzyl ketone, 22 g of ethyl orthoformate and 5 g of morpholine are boiled for 8 hours in 200 ml of dimethyl formamide. The ethanol formed during the reaction is removed through a fraction head. Then the major part of solvent is distilled off in vacuum and the residue is diluted with dilute aqueous hydrochloric acid. The crude product is filtered and recrystallized from acetone, yielding 24 g of 7-isopropyloxy-isoflavone of m.p. 115°-117°C.

1. customis removed through a fraction head
2. distillationThen the major part of solvent is distilled off in vacuum
3. additionthe residue is diluted with dilute aqueous hydrochloric acid
4. filtrationThe crude product is filtered
5. customrecrystallized from acetone