申请人:E. I. Du Pont de Nemours and Company
公开号:US04154737A1
公开(公告)日:1979-05-15
A process for the preparation of maleimides and dimaleimides in high yield, wherein in the first step maleic anhydride and a suitable primary amine or diamine are contacted at about 30.degree.-60.degree. C. in the presence of a simple, cheap organic solvent; and in the second step the thus-formed intermediate is cyclized, without prior isolation, at 45.degree.-60.degree. C. in the presence of a lower fatty acid anhydride, a tertiary amine having a pK.sub.a of at least 10 and of a salt of magnesium, lithium, manganese(II), or cobalt(II) soluble in the liquid reaction medium to the extent of at least 0.2 weight percent. Alternatively, the tertiary amine can be added in the first step. The product maleimide or dimaleimide normally can be isolated by filtration after cooling to room temperature. Water-miscible solvents may be diluted with water prior to product isolation. Certain N,N'-arylene-dimaleimides, which can be prepared by this process, are vulcanization adjuvants for elastomers.
一种制备马来酰亚胺和二马来酰亚胺的高产率工艺,其中在第一步中,在适当的一级胺或二级胺的存在下,在简单、廉价的有机溶剂的存在下,在约30℃至60℃下接触马来酸酐;在第二步中,在未先分离的情况下,在45℃至60℃的条件下,在低级脂肪酸酐、具有至少10的pK.sub.a的三级胺以及可溶于液体反应介质中至少0.2重量百分比的镁、锂、锰(II)或钴(II)的盐的存在下,使所形成的中间体环化。或者,三级胺可以在第一步中添加。通常,在冷却至室温后,可以通过过滤来分离产物马来酰亚胺或二马来酰亚胺。在分离产物之前,可以将水溶性溶剂稀释为水。通过该工艺可以制备某些N,N'-芳基二马来酰亚胺,该物质可用作弹性体的硫化助剂。