【作者】 王娟；

【导师】 陈小立； 朱泉；

【作者基本信息】 东华大学 ， 应用化学， 2005， 硕士

【摘要】 苯并噁唑类化合物具有广泛的生物活性,在农业上可以用作杀菌、除草和杀虫剂。2,6—二氯苯并噁唑是苯并噁唑的二氯取代物,是一种重要的有机合成中间体,广泛应用于制备农药、医药、染料等有机产品。因此,市场上对2,6—二氯苯并噁唑的需求日益扩大。我们应常州科莱博公司的要求对中间体2,6—二氯苯并噁唑的合成进行了研究。 本课题对2,6—二氯苯并噁唑的各种合成路线进行比较、实验和分析讨论得到了最佳的合成路线。最终的合成路线为:由邻氨基苯酚—尿素法合成苯并噁唑酮,以过氧化氢—盐酸为氯化剂对苯并噁唑酮的6位进行氯化,最后经五氯化磷氯化羰基得到2,6—二氯苯并噁唑。 合成路线示意图如下:更多还原

【Abstract】 Benzoxazole and its derivates have extensive biologic activity. They can be used as antiseptic, herbicide or insecticide on agriculture. 2, 6-dichlorobenzoxazole is di-chlorine substitute of benzoxazole, a very important intermediate.This paper relates to the processes for preparing the intermediate which can be employed for synthesis of active compounds, for example active compounds for crop protection agents, pharmaceuticals or dyestuff. As a result, the demand of 2,6-dichlorobenzoxazole is increasing.In this paper, 2, 6-dichlorobenzoxazole was prepared from cheap material o-aminophenol and urea in three steps. Firstly, the cyclization reaction of o-aminophenol with urea to give benzoxazolone is carried out in sulfuric acid. Secondly, the chlorination of benzoxazolone with hydrochloric and hydrogen peroxide is carried out in acetic acid. Lastly, the 6-chlorobenzolone is chloridized by phosphorus pentachloride in o-dichlorobenzene toget 2, 6-dichlorobenzoxazole.In contradistinction to the process hitherto known for preparing 2, 6-dichlorobenzoxazole, this paper is characterized by the fact that the yields are higher, the use of toxic and corrosive gases is avoided. Furthermore, the reaction products are so pure that it is unnecessary to precipitate or to recrystallize them. The simple procedure, higher yields and purity, and shorter reaction time are the advantages of the method.Structures of the products were primarily identified by TLC, IR and ’HNMR.更多还原