| 摘要 |
PURPOSE:To obtain the titled compound dihalomethylated at the 4-position selectively in reacting a p-substituted phenolic derivative with a haloform in the presence of sodium hydride, etc., by using cyclodextrin as a catalyst. CONSTITUTION:A p-substituted phenolic derivative, e.g. p-cresol, is reacted with a haloform in the presence of cyclodextrin, e.g. any of the alpha- or beta-cyclodextrin, as a catalyst and sodium hydroxide or potassium hydroxide to give the aimed compound expressed by formula III useful as an intermediate for physiologically active substances, etc. in a high selectivity of 90-100% with the formation of a compound expressed by formulas I and II (X is halogen; A-E are substituted or unsubstituted alkyl, allyl, alkoxyl or aryl) reduced to 10% or less based on the total amount of the product. Thus, the separating operation is very simple, and the aimed compound can be obtained in a high yield of 30-90%. |
