One-Step Catalytic Synthesis of Alkyl-Substituted Quinolines

Synthesis of 4-substituted 3-(2-hydroxyphenyl)-quinolines through an unexpected iron(iii) chloride promoted reaction of cyclic imine dibenzo[b,f][1,4]oxazepines with alkynes

An unexpected FeCl₃-promoted reaction of cyclic imine dibenzo[b,f][1,4]oxazepines with alkynes was studied to produce novel 4-substituted 3-(2-hydroxyphenyl)-quinolines with 34–88% yield.

Ytterbium(iii)-catalyzed three-component reactions: synthesis of 4-organoselenium-quinolines

4-Organoselenium-quinolines were synthesized via model multi-component Povarov reactions between p-anisidine, ethyl glyoxylate and ethynyl(phenyl)selane.

CuBr-ZnI2 Combo-Catalysis for Mild CuI-CuIII Switching and sp2 C-H Activated Rapid Cyclization to Quinolines and Their Sugar-Based Chiral Analogues: A UV-Vis and XPS Study

An unprecedented CuBr-ZnI₂ combo-catalyzed mild Cu¹-Cu^III switching activation of sp² C-H of highly electron-rich arenes is reported. Anilines, aldehydes, and terminal alkynes were rapidly coupled together at ambient temperature to construct a ubiquitous quinoline framework through cyclization of the C≡C bond. This smart solvent-free strategy was exploited for the direct synthesis of valuable 4-substituted, 2,4-disubstituted, and thermally labile sugar-based chiral quinolines in good yields. In contrast to the frequently used imine-alkyne cyclization reaction, this uncommonly mild Cu^I-Cu^III combo-catalysis for a rapid three-component cyclization is expected to proceed through the formation of a flexible propargyl amine intermediate, which provides a Cu^I-procatalyst for rapid sp² C-H activation with cyclization involving transient Cu^III species. The in situ generation of transient Cu^III species was confirmed through online ultraviolet-visible spectroscopy (UV-vis), electrospray ionization mass spectrometry (ESI-MS), and X-ray photoelectron spectroscopy (XPS) analyses.

Synthesis of quinolines through copper-catalyzed intermolecular cyclization reaction from anilines and terminal acetylene esters

A simple and convenient copper-catalyzed intermolecular cyclization reaction for the synthesis of quinolines from anilines and terminal acetylene esters has been developed.

Novel routes to quinoline derivatives from N-propargylamines

A walk around the new avenue to the synthesis of quinoline derivatives from N-propargylamines.

Microwave-assisted expeditious and efficient synthesis of novel quinolin-4-ylmethoxychromen-2- and -4-ones catalyzed by YbCl3 under a solvent free one-pot three component domino reaction and their antimicrobial activity

MW assisted multicomponent A³ synthesis was developed for the synthesis of quinolin-4-ylmethoxychromen-2- and -4-ones in high yields with YbCl₃ and reused efficiently for four times.

An efficient synthesis of quinolines via copper-catalyzed C–N cleavage

An efficient method to synthesize substituted quinolines from ketones and 2-amino benzylamines is described.

Aldehyde–alkyne–amine (A3) coupling catalyzed by a highly efficient dicopper complex

A dicopper(i) complex was developed as highly efficient catalyst for A³ coupling reactions, which led to the formation of propargylamines.

Metal free synthesis of 2,4-diarylquinoline derivatives with enamides and imines

A simple and efficient way to construct quinoline derivatives using enamides and imines in metal free condition.

ONO pincer type Pd(ii) complexes: synthesis, crystal structure and catalytic activity towards C-2 arylation of quinoline scaffolds

Four new palladium(ii) complexes featuring ONO pincer type hydrazone ligands were synthesized and characterized by spectroscopic and single-crystal XRD analysis. Utility of these complexes to catalyze C–C bond formation in quinoline scaffolds were assessed.

Synthesis of quinoxalines or quinolin-8-amines from N-propargyl aniline derivatives employing tin and indium chlorides

The utility of stannous chloride dihydrate as well as indium/InCl₃ in combination with “ortho-nitrogen”-N-propargylanilines for the construction of either quinoxaline- or quinolin-8-amine-scaffolds is demonstrated. Depending on the nature of the alkyne, different bicyclic nitrogen heterocycles are formed under aerobic conditions.