申请人:NEW JAPAN CHEMICAL CO.,LTD.
公开号:EP0421329A2
公开(公告)日:1991-04-10
Disclosed is a process for preparing a diacetal compound of the formula (I) such as a dibenzylidene sorbitol, comprising the steps of(i) condensing an aldehyde compound and a polyhydric alcohol in the presence of an acid catalyst and when required a lower alcohol in a hydrophobic organic solvent to give a reaction mixture containing a diacetal compound, (ii) neutralizing the reaction mixture, (iii) washing the mixture with water, (iv) removing the solvent from the mixture thus washed, and (v) drying the residual mass; the process being characterized in that an amine such as, for example, di(C₁₀-C₂₆ alkyl or alkenyl)amine substituted on the nitrogen atom with a C₁-C₄ alkyl group or with a group of the formula (̵C₂H₄O)qH wherein q is an integer of 1 to 4, or a (C₁₄-C₂₂ alkyl or alkenyl)amine substituted on the nitrogen atom with one or two groups of the formula (̵C₂H₄O)qH wherein q is 1 to 4, is added during the period from the formation of the reaction mixture to the completion of the drying step.
本发明公开了一种制备式(I)的二缩醛化合物(如二亚苄基山梨醇)的工艺,包括以下 步骤:(i)在酸催化剂存在下,必要时在低级醇存在下,在疏水性有机溶剂中缩合醛化合物 和多元醇,得到含有二缩醛化合物的反应混合物;(ii)中和反应混合物;(iii)用水洗涤混合物; (iv)从这样洗涤的混合物中除去溶剂;(v)干燥残留物;该工艺的特征在于胺,例如在氮原子上被 C₁-C₄ 烷基或式 (̵C₂H₄O)qH 的基团取代的二(C₁₀-C₂₆ 烷基或烯基)胺,其中 q 为 1 至 4 的整数、或(C₁₄-C₂₂烷基或烯基)胺,在氮原子上被一个或两个式(̵C₂H₄O)qH(其中 q 为 1 至 4)的基团取代,在反应混合物形成至干燥步骤完成期间加入。