Schiff Base-Pd II Complexes Containing Pyridine and Thiophene Rings: Synthesis, Characterization, Suzuki-Miyaura C-C Coupling Reactions

N ew Schiff base-palladium II complexes 1a-d were synthesized with the reaction of Schiff base ligand and [PdCl2 CH3CN 2]. Pd II complexes 1a-d were solid and stable to moisture and air. Their structures were characterized through the spectroscopic techniques including microanalysis, FT-IR, UV-Vis, proton 1H and carbon 13C NMR, mass spectrometry. The data obtained from the spectroscopic techniques showed that Schiff base-Pd II complexes 1a, 1b and 1c were formed through the coordination of azomethine nitrogen and carbonyl/hydroxyl oxygen atoms, while 1d complex coordinated only azomethine nitrogen atom of the Schiff base. All complexes were found to have square plane. In addition, Pd II complexes 1a-d were investigated in Suzuki-Miyaura coupling reactions of different aryl bromides using phenylboronic acid. The reactions were carried out in a mixed aqueous EtOH/H2O 1/3 at room temperature with K2CO3 as the base for 1 hour. The Pd II complexes 1a-d used as catalysts exhibited perfect catalytic activity in the Suzuki-Miyaura reactio

Synthesis, Characterization, and Antimicrobial Properties of a New Ligand and Its Pd(II), Ru(II), Fe(II), Co(II) Complexes

Schiff bases and their complexes are versatile compounds synthesized from the condensation of an amino compound with carbonyl compounds and widely used for industrial purposes and also exhibit a broad range of biological activities including antifungal, antibacterial, antimalarial, antiproliferative, antiviral, and antipyretic properties. In this study, the complexes of (E)-2-(3,5-di-tert-butyl-2-hydroxybenzylideneamino)-6-methyl4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile (L) with Co(II), Fe(II), Pd(II) and Ru(II) were successfully prepared. Structures of Schiff base and its metal complexes obtained were confirmed by FT-IR, 1H-NMR, 13CNMR, UV–vis, magnetic susceptibility, mass spectroscopy and elemental analysis. Antimicrobial activity of the synthesized Schiff base and its metal complexes have been studied. When the antimicrobial activities of the compounds were examined, it was observed that the lowest activity was exhibited by the ligand, and the highest activity was exhibited by the Co(II) and Pd(II) complexes. None of our compounds were been found to exhibit antifungal activity

Synthesis, characterization and antioxidant activity of Schiff base and its metal complexes with Fe(II), Mn(II), Zn(II), and Ru(II) ions: Catalytic activity of ruthenium(II) complex

The synthesis, spectral, catalytic and antioxidant properties of ethyl-2-(2-hydroxy-3-methoxybenzylideneamino)-6-methyl-4,5,6-tetrahydrobenzo[b]thiophene-3-carboxylate (L) substituted iron(II), manganese(II), zinc(II), and ruthenium(II)-arene chlorides are described for the first time. The ligand and its metal complexes were characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, and spectral (1H NMR, 13C NMR, FT-IR, UV-Vis and Mass) techniques. The FT-IR spectra showed that the ligand can act as bidentate or tridentate. Magnetic moments and electronic spectral studies revealed an octahedral geometry for all the complexes obtained. The thermal behavior of the complexes showed that the water molecules were separated in the first step followed immediately by decomposition of the anions and ligand molecules in the subsequent steps. Ru(II) complex was used as catalysts for the transfer hydrogenation of ketones. At the same time, the effect of various bases such as NaOH, KOH, KOBut and NaOAc as organic base were investigated in the transfer hydrogenation of ketones by 2-propanol as the hydrogen source. The complexes and ligand were tested in vitro for their antioxidant activity. The experimental results showed that Ru(II) complex had more potent antioxidant activities than Zn(II), Fe(II), Mn(II) complexes and parent ligand

Synthesis, Characterization, Thermal Study and Optical Property Evaluation of Co(II), Pd(II) Complexes Containing Schiff Bases of Thiophene-3-Carboxylate Ligand

In this study, a Schiff base ligand and its cobalt(II) and palladium(II) metal complexes were prepared. The structures of the obtained compounds were characterized through Fourier transform infrared spectroscopy, elemental analysis (microanalysis), ultraviolet–visible (UV–Vis) spectroscopy, proton (1H) and carbon (13C) nuclear magnetic resonance (1H-NMR, 13C-NMR), liquid chromatography–mass spectrometry (LC–MS), magnetic susceptibility measurements, thermogravimetric analysis and differential thermal analysis. UV spectra characteristics and basic optical parameters (e.g., absorbance band edge, optical band gap, refractive index and electrical conductance) of the ligand, Co(II) and Pd(II) complexes were investigated in dimethyl sulphoxide, N,N-dimethylformamide and ethanol (EtOH) solvents. The detailed analysis of the test results suggested that both the Pd(II) complex and, particularly, the Co(II) complex can be used in the preparation of diodes owing to their appropriate optical properties. © 2019, The Minerals, Metals & Materials Society

Ruthenium(II) complexes with pyridine-based Schiff base ligands: Synthesis, structural characterization and catalytic hydrogenation of ketones

This study investigated the synthesis and characterization of which the result of the reaction of Schiff base ligands containing pyridine with [RuCl2(p-cymene)]2. The spectroscopic techniques used for the characterization process were the elemental analysis, mass spectroscopy, FT-IR, UV–Vis and 1H and 13C NMR. The results showed that Ru(II) complexes occured through the coordination of azomethine N, carbonyl and hydroxyl O atoms of the ligands. Ru(II) complexes were utilized as catalysts for the transfer hydrogenation of a series of ketones in the i-propanol solution and in the presence of KOH. The catalytic reactions indicated that the Ru(II) complexes (1a-d) were effective catalysts in the transfer hydrogenation reaction. © 2019 Elsevier B.V

Ruthenium(II) half-sandwich complexes containing N-substituted 5-nitrobenzimidazole: Synthesis, structures and catalytic transfer hydrogenation of ketones

In this study,N-substituted 5-nitrobenzimidazole ligands were reacted with [RuCl2(p-cymene)]2  and the corresponding complexes  were prepared and their structure were elucidated by elemental analysis, IR and NMR spectroscopic techniques. The synthesized Ru(II) complexes  were tested as catalysts for the transfer hydrogenation (TH) of acetophenone to secondary alcohols in the presence of KOH using 2–propanol as a hydrogen source at 82 ºC. This complexes was found to be an active catalyst in the catalytic transfer hydrogenation of ketones

Ruthenium (II) Half-Sandwich Complexes Containing N-Substituted 5-Nitrobenzimidazole: Synthesis, Structures and Catalytic Transfer Hydrogenation of Ketones

Bu çalışmada N-koordineli 5-nitrobenzimidazol ligandlarının [RuCl2(p-simen)]2 metal tuzu ile reaksiyonlarında yeni altı kompleks bileşik hazırlandı ve yapıları, elemental analiz, IR ve 1H13C NMR spektroskopik tekniklerle aydınlatıldı. Sentezlenen Ru(II) kompleksleri, transfer hidrojenasyonu için katalizör olarak test edildi. Kompleksler, 80 °C?de KOH varlığında, çeşitli sübstitüe ketonların hidrojen transfer tepkimelerindeki katalitik aktiviteleri incelendi ve %100?e kadar bir dönüşüm gösterdi. Komplekslerin aktif katalizörler olduğu bulundu.In this study, N-substituted 5-nitrobenzimidazole ligands were reacted with [RuCl2(p-cymene)]2 and the corresponding a new six complex compound were prepared and their structure were elucidated by elemental analysis, IR and 1H13C NMR spectroscopic techniques. The synthesized Ru(II) complexes were tested as catalysts for the transfer hydrogenation. The complexes were examined for their efficiency as a catalyst in the transfer hydrogenation of varied of substituted ketones to alcohols in the presence of KOH, at 80 °C and exhibited a finest conversion up to %100. The complexes find out the active catalysts

Synthesis of Pd+2 complexes of Schiff bases containing methyl 2-amino-6-benzyl-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3-carboxylate and spectral and catalytic activities

Here in, ONS-donor atom containing Schiff base ligands (1, 2) was used to prepare 1a and 2a complexes. The Schiff base ligands were synthesized using 2?hydroxy-3-methoxysalicylaldehyde and 4-benzoxybenzaldehyde with methyl 2-amino-6-benzyl-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3-carboxylate as precursors in ethanol medium. Pd(II) complexes (1a, 2a) were prepared using the corresponding PdCl2(CH3CN)2 and Schiff base in a (1:1) molar proportion. The Schiff bases (1, 2) and their Pd(II) complexes (1a, 2a) were then identified via various analytical/spectroscopic methods (1H and 13C) NMR, UV- Vis spectra, FT-IR, mass, TGA and CHN to determine their molecular structures. Finally, the results obtained based on Suzuki-Miyaura and Mizoroki-Heck cross-coupling reactions show that electron-donating and electron-withdrawing substituents on the aryl halide might produce coupling products in excellent yield in the presence of 1a, 2a complexes (as catalysts) under optimum conditions. © 2022Muş Alparslan Üniversitesi: BAP-20-TBMY-4902–03This study was supported by Muş Alparslan University (Turkey) Research Fund (BAP-20-TBMY-4902–03). The authors thank the Institute of Science for their postgraduate studies and the Department of Chemistry of the Faculty of Arts and Sciences of Muş Alparslan University for the characterization of the compounds (FT-IR and UV-Vis Spectrophotometer analysis).This study was supported by Muş Alparslan University (Turkey) Research Fund (BAP-20-TBMY-4902–03). The authors thank the Institute of Science for their postgraduate studies and the Department of Chemistry of the Faculty of Arts and Sciences of Muş Alparslan University for the characterization of the compounds (FT-IR and UV-Vis Spectrophotometer analysis)

5-Nitrobenzimidazole containing Pd(II) catalyzed C-C cross-coupling reactions: The effect of the N-substituent of the benzimidazole structure on catalyst activity

WOS: 000469236000020A series of Pd(II) complexes (1a-e) were successfully synthesized by reaction of N-substituted 5-nitrobenzimidazole with [PdCl2(CNCH3)(2)] in toluene under argon reflux condition. Their catalytic activity in the Suzuki-Miyaura and Mizoroki-Heck coupling reactions were investigated. All these complexes were characterized by elemental analysis, H-1 NMR, C-13 NMR and IR spectroscopy. The catalytic activities of N-substituted 5-nitrobenzimidazole palladium (II) complexes were screened in Mizoroki-Heck and Suzuki-Miyaura coupling reactions. The reactions were optimized for the most suitable temperature, solvent and base system. The Pd(II) complexes exhibited good catalytic activity at the Mizoroki-Heck reaction. Additionally, the Suzuki-Miyaura showed relatively excellent activity at the coupling reaction. (C) 2019 Elsevier B.V. All rights reserved