Synthesis, Characterization and Termal Studies of Cu, Ni and Pd Complexes with New SNS Pincer Type Ligand Bearing Pyridine Ring

Abstract

The new SNS pincer type ligand 2,6-bis(((trifluoromethyl)phenyl)thio)methyl)pyridine (SNS) was synthesized from the reaction of 2,6-bischloropyridine and 2-trifluoromethylbenzenethiol at a ratio of 1:2. Copper (SNS-Cu(II)), nickel (SNS-Ni(II)) and palladium (SNS-Pd(II)) complexes were synthesized from the 1:1 reaction of ligand and Cu(II), Ni(II), Pd(II) chloride salts, respectively. SNS complexes were obtained by meridional bonding of the metal (M) in the center of the complexes to both the nitrogen (N) atom and two sulfur (S) atoms. The synthesized compounds were characterized by NMR (ligand only), UV-Vis, FT-IR spectroscopic techniques, elemental analysis, TGA-DTA, melting point determination method. The complexes have a five coordinated triangular bipyramidal geometric structure. In addition, the molar conductivity values of the complexes were observed to be between 1.07-1.62 μS/cm. The complexes do not have conductivity properties. When the TGA curves of the complexes were examined, it was observed that their thermal stability was Pd>Cu>Ni.

Keywords

• SNS Pincer type ligand
• Metal complex
• Characterization
• Thioether

Yeni Piridin Halkası Taşıyan SNS Pincer Tipi Ligand ile Cu, Ni ve Pd Komplekslerinin Sentezi, Karakterizasyonu ve Termal Çalışmaları

Abstract

2,6-biskloropiridin ve 2-triflorometilbenzentiyol'ün 1:2 oranında reaksiyonundan yeni SNS pincer tip ligand olan 2,6-bis(((triflorometil)fenil)tiyo)metil)piridin (SNS) sentezlenmiştir. Ligand ve sırasıyla Cu(II), Ni(II) ve Pd(II) klorür tuzlarının 1:1 oranında reaksiyonundan bakır (SNS-Cu(II)), nikel (SNS-Ni(II)) ve palladyum (SNS-Pd(II)) kompleksleri sentezlenmiştir. Komplekslerin merkezinde bulunan metalin (M), hem azot (N) atomuna hem de iki taraftan kükürt (S) atomlarına meridyonel olarak bağlanması ile SNS kompleksleri elde edilmiştir. Sentezlenen bileşikler NMR (sadece ligand), UV-Vis, FT-IR spektroskopik teknikleri, elementel analiz, TGA-DTA, erime noktası tayini yöntemi ile karakterize edilmiştir. Kompleksler beş koordinasyonlu üçgen bipiramidal geometrik yapıya sahiptir. Ayrıca komplekslerin molar iletkenlik değerlerinin 1.07-1.62 μS/cm arasında olduğu görülmüştür. Kompleksler iletkenlik özelliğine sahip değildir. Komplekslerin TGA eğrileri incelendiğinde, termal kararlılıklarının Pd>Cu>Ni olduğu gözlemlenmiştir.

Keywords

• SNS Pincer tip ligand
• Metal kompleks
• Karakterizasyon
• Tiyoeter

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