毕业论文

打赏
当前位置: 毕业论文 > 化学论文 >

基于甲亚胺叶立德的[3+2]和[3+3]环加成反应

时间:2020-06-21 17:50来源:毕业论文
摘要 含氮杂环化合物广泛存在于天然产物与药物分子当中,这类化合物往往具有独特的生物和药物活性,因此这类化合物的合成是获取药物先导分子的重要来源之一。本文通过甲亚胺叶立

摘要 含氮杂环化合物广泛存在于天然产物与药物分子当中,这类化合物往往具有独特的生物和药物活性,因此这类化合物的合成是获取药物先导分子的重要来源之一。本文通过甲亚胺叶立德参与的环加成反应构建了两类具有独特生物活性的含氮杂环骨架。 第一章, 我们介绍了甲亚胺叶立德参与的有机小分子催化的不对称 1,3-偶极环加成反应的研究现状。同时,介绍了本论文的研究目标和内容。 第二章,我们通过联烯参与的催化不对称 1,3-偶极环加成反应,对映选择性地构建了手性氧化吲哚螺吡咯骨架。在这个反应中,我们得到了一个环内含有 C=C双键的螺环氧化吲哚骨架,这与前人报道的联烯参与的 1,3-偶极环加成反应的结果明显不同。该方法不仅揭示了联烯可以作为 1,3-偶极环加成反应的亲偶极子,也成功实现了氧化吲哚螺吡咯骨架的构建。另外,该反应还首次实现了酮和联烯参与的催化不对称1,3-偶极环加成反应,为手性螺环氧化吲哚提供了新的合成方法。同时,拓宽了1,3-偶极环加成反应的研究内容,丰富了联烯参与的化学反应。 第三章, 我们通过原位生成的甲亚胺叶立德与醌亚胺单酮的[3+3]环加成反应,高化学选择性、高收率地构建了具有独特生物活性的二氢苯并噁嗪骨架(化学选择性比例高达  >95:5,  产率高达98%)。 该反应不仅代表第一例醌亚胺单酮参与的[3+3]环加成反应,而且为甲亚胺叶立德参与的[3+3]环加成反应提供了新的例子和含氧的亲偶极体,可以为构建二氢苯并噁嗪骨架提供有效的策略。 51465
毕业论文关键词:甲亚胺叶立德、环加成反应、串联反应、杂环骨架 
 Abstract   Nitrogen-containing heterocyclic compounds exist widely in natural products and drug molecules. These compounds tend to have unique biological and pharmacological activities. Therefore,  the synthesis of of this type of compounds  is an important source of lead molecules for drug development. In this dissertation,  two kinds of heterocyclic skeletons with unique biological activity were constructed  based on the  cycloaddition reactions of azomethine ylide. In the first chapter, we introduce the research  background  of the  organocatalytic asymmetric  1,3-dipolar cycloadditions (1,3-DC)  of azomethine ylide.  Besides, the research objectives and contents of this dissertation were also introduced.      In the  second  chapter,  we introduced the  enantioselective  construction of spiro[indoline-3,2’-pyrrole]  framework via catalytic asymmetric 1,3-dipolar cycloadditions using allenes as equivalents of alkynes. In this allene-involved 1,3-DC, an unexpected spirooxindole framework bearing an intra-annular C=C double bond was generated, which is  quite different from previously reported 1,3-DCs of allenes. This approach not only confronted the great challenge in using allenes as dipolarophiles of 1,3-DCs, but also provided a unique strategy of using allenes as equivalents of alkynes to construct spiro[indoline-3,2’-pyrrole] structure. Besides, this reaction also represents the first catalytic asymmetric ketone-involved 1,3-DCs of allenes, which will also greatly enrich the research contents of 1,3-DCs, the chemistry of allenes as well as the synthetic methods of spirooxindoles.   In the third chapter, we introduced a chemoselective [3+3] cycloaddition of in situ generated azomethine ylides with  quinone monoimides (QMIs), which efficiently constructed six-membered   dihydrobenzoxazine frameworks with biological relevance in excellent chemoselectivities and high yields (up to >95:5  cr, 98% yield). This reaction not only represents the first  [3+3] cycloaddition of QMIs, but also provides a new example for [3+3] cycloadditions of azomethine ylides by using oxygen-contained dipolarophiles, which will serve as a useful strategy in constructing dihydrobenzoxazine scaffold.  基于甲亚胺叶立德的[3+2]和[3+3]环加成反应:http://www.lwfree.com/huaxue/lunwen_55096.html
------分隔线----------------------------
推荐内容