【作者】 魏颖；

【导师】 梁福顺；

【作者基本信息】 东北师范大学 ， 有机化学， 2014， 博士

【摘要】 N-溴代丁二酰亚胺(NBS)是有机合成重要的溴代试剂。通常NBS作为Br+源，参与亲电加成反应；还可以作为溴自由基源，参与自由基取代反应。一般来说,在反应中比较惰性的丁二酰亚胺通常作为副产物被分离。从原子经济性角度考虑，希望将NBS中的丁二酰亚胺负离子直接嵌入到目标分子中，实现NBS双功能化作用，既作溴源又作胺源是化学合成者所追求的。本论文通过发展了新颖的、高效地串联反应，为多取代呋喃并吡啶酮、5-氨基-3(2H)-呋喃酮、α-氧代酰胺、α-胺基酮、β-胺基酮以及烯丙基胺化合物的合成提供了新方法。同时，对反应机理进行了深入的研究。所采用的方法具有反应条件温和、原料易得和高的原子经济性等优点。论文共分八个章节。第一章综述了N-溴代丁二酰亚胺(NBS)在有机反应中的应用。第二章提出了本论文的选题依据。第三章研究了温和条件下，1-烯酰基-1-酰胺基环丙烷与NBS/HCOOH组合经由溴鎓离子引发的亲电串联反应，高效地合成了呋喃并吡啶酮和5-氨基-3(2H)-呋喃酮类化合物。这一高效地串联转变涉及连续的C Br形成及断裂、C N形成、C C断裂及形成和C O形成。该反应通过卤活化首次实现了在α,β-不饱和烯酮体系中的1,2-芳基迁移。第四章我们发展了一种1-乙酰基-1-酰胺基环丙烷与NXS/RCOOH组合经由溴鎓离子引发的亲电串联反应，简洁、高效地合成了5-氨基-3(2H)-呋喃酮类化合物。该反应通过原位生成的溴鎓离子，使得羰甲基极性翻转由亲核中心变为亲电中心(极性翻转策略)，引发羰甲基与N-烷基酰胺氧分子内亲电环合，实现C–O键的构建。第五章发展了一种简单、高效地合成具有重要生物活性α-氧代酰胺的新方法。与传统方法相比，避免了使用有毒、稀少的贵金属和苛刻的反应条件。在反应过程中我们利用DMF作为胺源和溶剂，简化了反应操作，充分体现了原子经济性这一原则。第六—八章发展了一种N-溴代酰亚胺/DBU组合作为原子经济性和通用的胺化试剂。在温和条件下，芳基烷基酮、查尔酮和烯烃在NBS(P)/DBU组合作用下，分别生成α-胺基酮、β-胺基酮和烯丙基胺类化合物。提出DBU双活化机制，即DBU与N-溴代酰亚胺之间通过卤键相互作用形成N―Br┄N不对称卤键加合物，进一步形成更亲电的溴物种和提供一种潜在的氮亲核体。在反应体系中NBS(P)起到双功能作用，既作溴源又作胺源。实现了比较惰性的丁二酰亚胺(邻苯二甲酰亚胺)负离子直接嵌入到目标分子中。更多还原

【Abstract】 N-Bromosuccinimide (NBS) is a versatile reagent for synthetic organic chemistry.Traditionally, NBS can be considered as a convenient source of either cationic bromine usedin electrophilic addition reactions or bromine radical used in radical substitution reactions. Ingeneral, relatively inert succinimide would be generated as a by-product in the reaction. Fromthe atom economic point of view, direct installation of the succinimido moiety of NBS intothe target molecules, as well as further transformation thereby, is highly desirable. The dualrole of NBS providing both electrophilic bromine and nucleophilic nitrogen sources is thepersuit of chemists.In this thesis, we have developed novel and efficient cascade reactions for the synthesisof polysubstituted dihydrofuropyridinones,5-amino-3(2H)-furanones, α-ketoamides,α-aminoketones, β-aminoketones and allylic amine derivatives. Mechanisms of these newreactions are also investigated in details. These methods have apparent advantages, such asmild reaction conditions, readily available starting materials and high atom economy and soon.The thesis is divided into eight chapters. In chapter one, The application ofN-bromosuccinimide in organic reactions is reviewed. The thesis proposal is presented inchapter two.Chapter three, under mild conditions, bromonium ion initiated electrophilic cascadereaction of1-alkenoylcyclopropane carboxamides with NBS/HCCOH comdination wasdeveloped, which led to the production of dihydrofuropyridinones and5-amino-3(2H)-furanones. Such an efficient one-pot cascade transformation involves sequential C–Brformation and cleavage, C–N formation, C–C cleavage and formation, and C–O formation.The1,2-aryl migration involved in the reaction, to the best of our knowledgement, representsthe first example in α,β-unsaturated enone system via halogen activation.Chapter four we have developed a practical and efficient protocol for the production ofhighly functionalized5-amino-3(2H)-furanones by the bromonium ion initiated electrophiliccascade reactions of1-acetylcyclopropane-carboxamides with NXS/RCOOH combination.Through in situ generated haloniumion intermediates, the reactivity of the α-carbon to thecarbonyl group was converted from originally nucleophilic into electrophilic (umpolungstrategy), leading to the formation of a C O bond with an amide oxygen atom viaintramolecular electrophilic cyclization.Chapter five we have developed a simple and efficient new method for the synthesis of biologically important α-ketoamides. This protocol avoided the use of expensive catalyst andharsh conditions generally adopted in the conventional method. In the whole process, DMFfunctions as nitrogen sources and solvent, which simplifies reaction and fully embodies atomeconomy.In chapter six―eight, as a general and practical animation reagent, a combination ofN-bromoimide and DBU has been developed. Under mild conditions, aryl alkyl ketones,chalcones and alkenes lead to α-imidoketones, β-imidoketones and allyl amines, respectively,with an NBS(P)/DBU combination. The mechanism of dual activation of DBU that DBU andN-bromoimide formN―Br┄N asymmetric halogen bonding adducts via halogen bonding andlead to more electrophilic bromine and more nucleophilic nitrogen atoms simultaneously, wasproposed. In the reaction system, NBS(P) can play dual roles by act as both bromine andnitrogen sources. Relatively inert succinimide/phthalimide can being installed directly in thetarget molecule.更多还原