The aza-xylylene Diels-Alder approach for the synthesis of naturally occurring 2-alkyl tetrahydroquinolines

The recently discovered intramolecular aza-xylylene Diels-Alder reaction, based on a 1,4-dehydrohalogenation reaction, was extended in terms of substrates and leaving groups allowing the assembly of tetrahydroquinolines in two synthetic steps. Intramolecular cleavage of a thiocarbamate using triphenylphosphine and tetrachloromethane (Appel conditions) to give chloromethyl phenylisocyanate has been presented for the first time. The synthetic feasibility of this process was demonstrated in the first total syntheses of the alkaloids rac-Angustureine and 1-methyl-2-propyltetrahydroquinoline.     

A Direct CH/ArH Coupling Approach to Oxindoles,Thio‐oxindoles, 3,4‐Dihydro‐1 H‐quinolin‐2‐ones,and 1,2,3,4‐Tetrahydroquinolines

A copper(II)‐catalysed approach to oxindoles, thio‐oxindoles, 3,4‐dihydro‐1H‐quinolin‐2‐ones, and 1,2,3,4‐tetrahydroquinolines via formal C?H, Ar?H coupling is described. In a new variant, copper(II) 2‐ethylhexanoate has been identified as an inexpensive and efficient catalyst for this transformation, which utilises atmospheric oxygen as the re‐oxidant.     

Reactions of 1,5-Diketones with Ammonia and Its Derivatives. (Review)

Published data and the authors' own experimental results on the reaction of aliphatic, semicyclic, and oxosemicyclic 1,5-diketones and alkylidene- and arylidene-2,2-dicyclanones with ammonia, ammonium acetate, and XNH₂ derivatives, where X = Alk, Ar, OH, NH₂, PhNH, ArCONH, and CHO, are reviewed. The characteristics and the relationships governing the transformations into azaheterocycles in relation to the nature of the reagents and the reaction conditions are discussed.     

烯酰胺参与的不对称Povarov反应研究进展

烯酰胺因其氮活化的碳碳双键在各类含氮化合物的合成中具有潜在应用价值,其中有机催化的α,β-双官能化反应在有效骨架的构建中得到了广泛使用。烯酰胺参与的Povarov反应作为邻位双官能化反应的扩展应用,为4-氨基-1,2,3,4-四氢喹啉的构建提供一条简洁高效的途径。尽管该类反应如此重要,直到最近才开发出几种高效的不对称催化方案,本文将对这些研究进展进行总结。     

Iron‐Catalyzed Intramolecular Aminations of C(sp3)−H Bonds in Alkylaryl Azides

The nucleophilic iron complex Bu₄N[Fe(CO)₃(NO)] (TBA[Fe]) catalyzes the direct intramolecular amination of unactivated C(sp³)−H bonds in alkylaryl azides, which results in the formation of substituted indoline and tetrahydroquinoline derivatives.     

Samarium Triflate as Mild and Efficient Catalyst for Aza-Diels–Alder Reaction: A Facile Synthesis of cis-Fused Pyrano- and Furanoquinolines

Three-component coupling reactions of aldehydes, amines, and cyclic enol ethers have been carried out in the presence of samarium triflate to afford the corresponding pyrano and furanoquinolines in excellent yields with high endo-selectivity. The reaction conditions are mild and amenable to scale-up.     

Biological Properties of New Chiral 2-Methyl-5,6,7,8-tetrahydroquinolin-8-amine-based Compounds

The synthesis of a small library of 8-substituted 2-methyl-5,6,7,8-tetrahydroquinoline derivatives is presented. All the compounds were tested for their antiproliferative activity in non-cancer human dermal microvascular endothelial cells (HMEC-1) and cancer cells: human T-lymphocyte cells (CEM), human cervix carcinoma cells (HeLa), human dermal microvascular endothelial cells (HMEC-1), colorectal adenocarcinoma (HT-29), ovarian carcinoma (A2780), and biphasic mesothelioma (MSTO-211H). Compounds 3a, 5a, and 2b, showing significant IC₅₀ values against the whole panel of the selected cells, were further synthesized and tested as pure enantiomers in order to shed light on how their stereochemistry might impact on the related biological effect. The most active compound (R)-5a was able to affect cell cycle phases and to induce mitochondrial membrane depolarization and cellular ROS production in A2780 cells.