Come full circle: A method for the nucleophilic amination of methoxy arenes was established by using sodium hydride (NaH) in the presence of lithium iodide (LiI). This method offers an efficient route to benzannulated nitrogen heterocycles. Mechanistic studies showed that the reaction proceeds through an unusual concerted nucleophilicaromaticsubstitution.
Reductive Alkylation of Quinolines to <i>N</i>-Alkyl Tetrahydroquinolines Catalyzed by Arylboronic Acid
作者:Priyanka Adhikari、Dipanjan Bhattacharyya、Sekhar Nandi、Pavan K. Kancharla、Animesh Das
DOI:10.1021/acs.orglett.1c00302
日期:2021.4.2
A boronic acid catalyzed one-pot tandem reduction of quinolines to tetrahydroquinolines followed by reductivealkylation by the aldehyde has been demonstrated. This step-economcial synthesis of N-alkyl tetrahydroquinolines has been achieved directly from readily available quinolines, aldehydes, and Hantzsch ester under mild reaction conditions. The mechanistic study demonstrates the unique behavior
Transfer hydrogenation of pyridinium and quinolinium species using ethanol as a hydrogen source to access saturated N-heterocycles
作者:Suman Yadav、Dhananjay Chaudhary、Naveen Kumar Maurya、Dharmendra Kumar、Km Ishu、Malleswara Rao Kuram
DOI:10.1039/d2cc00241h
日期:——
Catalytic transfer hydrogenation (TH) for the reduction of heterocycles is an emerging strategy for accessing biologically active saturated N-heterocycles. Herein, we report a TH protocol that utilizes ethanol as a renewable hydrogen source and an Ir catalyst for the reduction of quinolines and pyridines. The reaction is promoted by simple amides as ligands.
用于还原杂环的催化转移氢化 (TH) 是获得具有生物活性的饱和 N-杂环的新兴策略。在此,我们报告了一种 TH 协议,该协议利用乙醇作为可再生氢源和 Ir 催化剂来还原喹啉和吡啶。该反应通过简单的酰胺作为配体来促进。
Metal-free transfer hydrogenation/cycloaddition cascade of activated quinolines and isoquinolines with tosyl azides
作者:Suman Yadav、Ruchir Kant、Malleswara Rao Kuram
DOI:10.1039/d3cc01430d
日期:——
difficulty in isolating cyclic enamines emanating from their intrinsic instability has impeded their exploration in cycloaddition reactions. Here, we achieved a metal-free domino reaction providing quinoline and isoquinoline-derived cyclic amidines by the cycloaddition of azides with in situ generated enamines via dearomatization.