申请人:Elnagar Y. Hassan
公开号:US20050049420A1
公开(公告)日:2005-03-03
The process enables highly effective N-halogenation of a compound having one or more halogenatable amido or imido functional groups in the molecule. The process involves, for example, concurrently feeding into a reactor (i) water, inorganic base, and the compound to be N-halogenated, e.g., a hydantoin, and a feed of (ii) a brominating agent and/or a chlorinating agent. The proportions of these feeds are such that the pH is kept at 5 or below or within a specified range e.g., 5.5-8.5 and one or more of the amido or imido nitrogen atoms is substituted by a bromine or chlorine atom. A feature of the process is that it can be conducted at elevated temperatures as high as about 90° C. without appreciable thermal decomposition of reactants or product. The resultant product continuously precipitates in high yield and purity. Moreover, products can be produced that are very pale yellow to almost pure white in appearance. Further, the process has been found capable of producing 1,3-dibromo-5,5-dimethylhydantoin with far larger particle sizes than previously produced on a commercial basis.
该过程可实现分子中具有一个或多个可卤化酰胺或亚胺官能团的化合物的高效N-卤代反应。该过程包括同时投入(i)水、无机碱和待N-卤代化的化合物(例如,一种咪唑啉)到反应器中,以及(ii)溴化剂和/或氯化剂的进料。这些进料的比例使得pH保持在5或以下或在特定范围内,例如5.5-8.5,并且一个或多个酰胺或亚胺氮原子被溴或氯原子取代。该过程的一个特点是,它可以在高达约90°C的升温条件下进行,而不会出现反应物或产物的明显热分解。所得产物以高收率和纯度连续沉淀。此外,可以生产外观非常淡黄色到几乎纯白色的产品。此外,该过程已被发现能够生产比以前商业生产的1,3-二溴-5,5-二甲基咪唑啉具有更大颗粒大小的产物。