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The synthesis of a series of 2- and 8-substituted 4-amino-7-chloroquinolines is presented. Starting from 4,7-dichloroquinolines, the chloro in the 4-position can be effectively substituted using amino alcohols to yield novel analogues of the antimalarial (hydroxy)chloroquine. Both short-chain (2-aminoethanol) and long-chain (5-[N-ethyl-N-(2-hydroxyethyl)amino]-2-aminopentane) coupling partners can be used. While ketone and nitro functionalities were found to be incompatible with the coupling conditions, electron-donating amino and dimethylamino substituents were tolerated. In addition to characterization in solution using multinuclear NMR spectroscopy and high-resolution mass spectrometry, single-crystal X-ray structures are presented of two 4,7-dichloroquinolines as well as three of the N-alkylated products including a unique species in which a pyrrole heterocycle formed at the 2-position of the quinoline subunit and a rare example of a 4-aza-1,10-phenanthroline. Key words: chloroquine analogues, quinoline synthesis, X-ray crystallography, Introduction Quinoline (benzo[b]pyridine) is a prominent pharmacophore, appearing in numerous biologically active synthetic molecules and natural products including prominent antimalarials such as the cinchona alkaloid quinine and the clinically critical [...]

An N-heterocyclic carbene ligand precursor bearing a p-extended phenanthridine (3,4-benzoquinoline) unit is presented. The proligand was isolated as the imidazolium salt of chloride (1*HCl), bromide (1*HBr), or hexafluorophosphate (1*[HPF.sub.6]) counterions. These salts can be deprotonated and the carbene installed on silver centres using [Ag.sub.2]O as both a base and a source of metal ion. The resulting Ag(I) complex (1)AgCl can be used in a transmetalation reaction to generate a Pd(II) coordination complex (1)Pd([CH.sub.3]CN)[Cl.sub.2]. The characterization and photophysical properties of these complexes is presented, along with a demonstration of the utility of (1)Pd([CH.sub.3]CN)[Cl.sub.2] in mediating a catalytic C-N cross-coupling reaction for the preparation of the pharmaceutical Piribedil. Key words: N-heterocyclic carbenes, phenanthridine, ligand design, transmetalation, piribedil. Nous presentons un precurseur de ligand carbene Nheterocyclique portant une unite phenanthridine (3,4-benzoquinoline) a systeme p etendu. Ce proligand a ete isole sous forme de sel d'imidazolium avec les contre-ions chlorure (1*HCl), bromure (1*HBr) ou hexafluorophosphate (1*[HPF.sub.6]). Ces sels peuvent etre deprotones pour installer le carbene sur un centre d'argent a l'aide de [lAg.sub.2]O, employe a la fois comme base et comme source d'ion metallique. Le complexe dAg(I) resultant, (1)AgCl, peut etre utilise dans une reaction de transmetallation pour generer un complexe de coordination de Pd(II) de formule (1)Pd([CH.sub.3]CN)[Cl.sub.2]. Nous presentons la caracterisation et les proprietes photophysiques de ces complexes, et nous demontrons l'utilite du complexe (1)Pd([CH.sub.3]CN)[Cl.sub.2] dans la catalyse d'une reaction de couplage croise C-N pour la preparation du compose pharmaceutique piribedil. [Traduit par la Redaction] Mots-cles: carbenes N-heterocycliques, phenanthridine, conception de ligand, transmetallation, piribedil., Introduction N-Heterocyclic carbenes (NHCs) are a well-established and versatile class of ligand in coordination chemistry, (1) known mainly as strong r-donors but with widely tunable steric and electronic properties. (2) [...]

Meso‐nitrile oxide group in 1,7‐Diphenyl‐containing BODIPYs can be involved in highly unusual [3+2] intramolecular cycloaddition reaction with the formation of the dihydrobenzo[d]isoxazole‐containing BODIPYs. Oxidation of these compounds results in the formation of unprecedented either benzisoxazole‐ or benzo[b]azepine‐fused fully conjugated NIR absorbing BODIPYs. The photophysical properties and electronic structures of the target compounds were studied by an array of experimental and theoretical methods. [ABSTRACT FROM AUTHOR]

A series of four-coordinate zinc(II) complexes is presented in which the amido vs. imino character of a ligated nitrogen donor correlates to the luminescence intensity. DFT analysis points to a distinct mechanism for this trend wherein emission can be switched on by restricting non-radiative decay pathways through the resonance-induced delocalization of amido ligand lone-pairs. [ABSTRACT FROM AUTHOR]

This article discusses the development of a clinical compound, PF-06842874, for the treatment of Pulmonary Arterial Hypertension (PAH). The authors focus on the synthesis of the compound and the challenges faced in the process, such as low purity and the use of undesirable solvents. They explore different coupling methods and identify a Pd-catalyzed Buchwald-Hartwig coupling as the most effective approach. The article provides valuable insights into the development of a potential treatment for PAH and describes a robust and scalable process for the synthesis of the compound. [Extracted from the article]