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