Preparation process of N-substituted maleimides
    1.
    发明公开
    Preparation process of N-substituted maleimides 失效
    Verfahren zur Herstellung von N-substitutionierten Maleinimiden。

    公开(公告)号:EP0403240A1

    公开(公告)日:1990-12-19

    申请号:EP90306417.8

    申请日:1990-06-13

    CPC分类号: C07D207/448

    摘要: A process for the preparation of N-substituted maleimides by conducting heat-dehydration and dehydrating imidization of N-substituted maleamic acids under azeotropic distillation of generated water in a solvent mixture containing a solvent capable of forming water azeotrope and an organic aprotic polar solvent, in the presence as catalyst of metallic tin, tin oxide, a tin salt of a maleamic acid or a tin compound which forms a tin salt of the N-­substituted maleamic acid in the reaction system.
    E.G. N-phenylmaleamic acid (produced in situ from aniline and maleic anyhydride) in xylene and dimethylformamide is converted to N-phenylmaleimide using as a catalyst stannous oxide (0.025 mole per mole of maleic anhydride).

    摘要翻译: 在含有能够形成水共沸物和有机非质子极性溶剂的溶剂的溶剂混合物中,在产生的水的共沸蒸馏下进行N-取代的马来酰胺酸的热脱水和脱水酰亚胺化,制备N-取代的马来酰亚胺的方法, 在反应体系中形成金属锡,氧化锡,马来酰胺酸的锡盐,形成N-取代的马来酰胺酸的锡盐的锡化合物的催化剂的存在。 例如。 使用氧化亚锡(0.025摩尔/摩尔马来酸酐)将N-苯基马来酸(在苯胺和马来酸酐中原位产生)在二甲苯和二甲基甲酰胺中转化为N-苯基马来酰亚胺。