A Novel Mechanistic Study on Ultrasound-Assisted, One-Pot Synthesis of Functionalized Benzimidazo[2,1-<i>b</i>]quinazolin-1(1<i>H</i>)-ones
作者:Li-Hsun Chen、Tsai-Wen Chung、Bharat D. Narhe、Chung-Ming Sun
DOI:10.1021/acscombsci.5b00186
日期:2016.3.14
Ultrasound-assisted synthesis of benzimidazo[2,1-b]quinazolin-1(1H)-ones was achieved via piperidine-catalyzed three-component reaction of 2-aminobenzimidazoles, an aromatic aldehyde, and 1,3-dione in aqueous isopropanol. This mechanism was first suspected following our identification of unusual reaction intermediates in a one-pot reaction. An unprecedented coupling reaction, it involved a nucleophilic
通过哌啶催化的2-氨基苯并咪唑,芳香族醛和1,3-二酮在异丙醇水溶液中的三组分反应实现苯并咪唑并[2,1 - b ]喹唑啉-1(1 H)-的超声辅助合成。在我们确定了一锅反应中不寻常的反应中间体之后,首先怀疑了这种机制。前所未有的偶联反应,它涉及2-氨基苯并咪唑对原位生成的迈克尔加合物的亲核攻击,然后发生电环形成反应。与普遍接受的机理相反,2-氨基苯并咪唑与Knoevenagel加合物的直接反应不能释放目标化合物。
Decarboxylative <i>ipso</i>
Amination of Activated Benzoic Acids
作者:Martin Pichette Drapeau、Janet Bahri、Dominik Lichte、Lukas J. Gooßen
DOI:10.1002/anie.201812068
日期:2019.1.14
the ligand and either air or N‐methylmorpholine N‐oxide as the oxidant, electron‐deficient benzoic acids undergo oxidative decarboxylative coupling with unprotected amines. This operationally simple aniline synthesis is widely applicable with respect to the amine and gives good yields, even on multigram scale. The orthogonality of this reaction to other Pd‐catalyzedcross‐couplings allows the concise
3D-Printed Polypropylene Continuous-Flow Column Reactors: Exploration of Reactor Utility in S<sub>N</sub>
Ar Reactions and the Synthesis of Bicyclic and Tetracyclic Heterocycles
FlowSyn continuous-flow reactor. Reactor utility was explored in reactions ranging from SNAr reactions to formation of complex heterocycles. It was shown that they are an inexpensive source of reactors for continuous flow, facilitating the synthesis of a range of heterocycles.
设计低成本的惰性聚丙烯(PP)连续流反应器并进行3D打印,以用于FlowSyn连续流反应器。在从S N Ar反应到复杂杂环形成的反应中探索了反应器的效用。结果表明,它们是连续流动反应器的廉价来源,可促进一系列杂环的合成。
Rhodium-Catalyzed Regioselective Synthesis of Isocoumarins through Benzothiadiazine-Fused Frameworks
作者:Prashant B. Dalvi、Kuang-Ling Lin、Manohar V. Kulkarni、Chung-Ming Sun
DOI:10.1021/acs.orglett.6b01408
日期:2016.8.5
An unprecedented two-step, one-pot synthesis of benzimidazothiadiazine 5,5-dioxides is presented. Reaction condition based regioselectivity has been achieved where fused benzimidazo[1,2-b][1,2,4]thiadiazines are exclusively formed under thermal conditions, whereas benzimidazo[2,1-c][1,2,4]thiadiazines were created only under microwave irradiation. The salient features of this protocol include a regioselective
提出了前所未有的两步,一锅法合成苯并咪唑并二嗪5,5-二氧化物。当在热条件下仅形成稠合的苯并咪唑[1,2- b ] [1,2,4]噻二嗪时,已经达到了基于反应条件的区域选择性,而苯并咪唑[2,1- c ] [1,2,4]噻二嗪则在热条件下形成。仅在微波辐射下产生。该方案的显着特征包括2-氨基苯并咪唑与邻卤代磺酰氯的区域选择性磺酰化,随后形成NC键。这些稠合的区域异构体的酸形式已用于引入新型的含胍的异香豆素骨架。
Synthesis of Aminofuran-Linked Benzimidazoles and Cyanopyrrole-Fused Benzimidazoles by Condition-Based Skeletal Divergence
作者:Wei-Shun Hsu、Min-Huan Tsai、Indrajeet J. Barve、Gorakh S. Yellol、Chung-Ming Sun
DOI:10.1021/acscombsci.7b00052
日期:2017.7.10
skeletal divergent synthesis was explored to achieve skeletal diversity in two component condensation reaction. Cyanomethyl benzimidazole was reacted with α-bromoketone under thermal conditions to furnish 2-aminofuranyl-benzimidazoles, while the same reaction afforded 3-cyano-benzopyrrolo-imidazoles under microwave irradiation. Two nonequivalent nucleophilic centers on benzimidazole moiety were manipulated