Beyond the Simple Copper(II) Coordination Chemistry with Quinaldinate and Secondary Amines

Abstract

Copper(II) acetate has reacted in methanol with quinaldinic acid (quinoline-2-carboxylic acid) to form [Cu(quin)2(CH3OH)]∙CH3OH (1) (quin− = an anionic form of the acid) with quinaldinates bound in a bidentate chelating manner. In the air, complex 1 gives off methanol and binds water. The conversion was monitored by IR spectroscopy. The aqua complex has shown a facile substitution chemistry with alicyclic secondary amines, pyrrolidine (pyro), and morpholine (morph). trans-[Cu(quin)2(pyro)2] (2) and trans-[Cu(quin)2(morph)2] (4) were obtained in good yields. The morpholine system has produced a by-product, trans-[Cu(en)2(H2O)2](morphCOO)2 (5) (morphCOO− = morphylcarbamate), a result of the copper(II) quinaldinate reaction with ethylenediamine (en), an inherent impurity in morpholine, and the amine reaction with carbon dioxide. (pyroH)[Cu(quin)2Cl] (3) forms on the recrystallization of [Cu(quin)2(pyro)2] from dichloromethane, confirming a reaction between amine and the solvent. Similarly, a homologous amine, piperidine (pipe), and dichloromethane produced (pipeH)[Cu(quin)2Cl] (11). The piperidine system has afforded both mono- and bis-amine complexes, [Cu(quin)2(pipe)] (6) and trans-[Cu(quin)2(pipe)2] (7). The latter also exists in solvated forms, [Cu(quin)2(pipe)2]∙CH3CN (8) and [Cu(quin)2(pipe)2]∙CH3CH2CN (9). Interestingly, only the piperidine system has experienced a reduction of copper(II). The involvement of amine in the reduction was undoubtedly confirmed by identification of a polycyclic piperidine compound 10, 6,13-di(piperidin-1-yl)dodecahydro-2H,6H-7,14-methanodipyrido[1,2-a:1′,2′-e][1,5]diazocine.

Top-Down N-Doped Carbon Quantum Dots for Multiple Purposes: Heavy Metal Detection and Intracellular Fluorescence

“…The different behaviors of N-CQDs-40 min and N-CQDs-15 h with respect to Cr 3+ and Cu 2+ can be correlated with the larger presence of amine groups on N-CQDs-15 h, which may have given a more specific interaction, i.e., a larger affinity toward N-derivatives as compared to the other probed ions, such as in Reinecke’s salt (NH 4 [Cr(NCS) 4 (NH 3 ) 2 ]·H 2 O) or other stable Cr 3+ complexes with N-derivatives, which can form with multiple bonds [ 54 ]. Similarly, Cu 2+ may undergo a substitution of oxygen-dented ligands bonded to Cu 2+ by nitrogen-dented ones [ 55 ], thus shifting the selectivity as well.…”

Hydrogen Bonding and Polymorphism of Amino Alcohol Salts with Quinaldinate: Structural Study

“…In the case of the 2-amino-1-butanol reagent, a racemic mixture was used. The copper starting material, [Cu(quin)2(H2O)], was synthesized as previously reported [24]. Infrared (IR) spectra were recorded with the ATR module in the 4000-400 cm −1 spectral range on a Bruker Alpha II FT-IR spectrophotometer (Bruker, Manhattan, MA, USA).…”

Synthesis of nanostructured cupric oxide for visible light assisted degradation of organic wastewater pollutants

“…The experiments were carried out in a 100 mL capacity glass photochemical reactor using a 400 Watt (W) medium pressure mercury visible light source. A solution (200 ml) containing Rhodamine B dye (0.01 g) was used by mixing the dye with distilled water subsequent to H 2 O 2 (1.5 ml) addition as a mediator for increased free radical generation to enhance the photodegradation process using nanostructured CuO as a semiconductor (Modec et al, 2020). A suspension using 0.1 g of the as prepared CuO nanoparticles in distilled water (50 mL) was prepared separately to which a dye solution (30 ml) was added prior to visible light irradiation.…”

“…From Figure 1(a), it can be discovered that for the CuO specimen prepared utilizing the nitratebased precursor (CuO-N60), the most compactly packed crystal planes (preferential crystallographic plane for the growth of crystals) are the {111}. This could be attributed to that fact that the copper oxide keeps up the majority of its mainstay structure, which begins from a principal metallic copper crystal lattice (Modec et al, 2020) in which the {111} planes are the most compactly packed. For the sulphate precursor-based CuO nanoparticles (CuO-S60), the predominant preferential crystal growth was along the {002}/{-111} plane.…”