ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Polyoxometalate based hybrids: synthesis of metal complexes and investigation of their electrochemical, thermal and biological properties

Seyit Ali Güngör, Mete Karaboyun, Ferhan Tümer, Sevil Toroğlu, and Mehmet Tümer

Chemistry Department, Science Faculty, Kahramanmaraş Sütçü İmam University, Kahramanmaraş, Turkey

E-mail: mtumer@ksu.edu.tr

Received: 23 January 2024  Accepted: 14 May 2024

Abstract:

The hybrid compounds (KL¹–KL³) based on Keggin polyoxometalate (POM) were synthesized from the reaction between azo-imine ligands (HL¹–HL³) and Keggin-type POM. Characterizations of the obtained compounds were done by elemental analyses, FTIR, MALDI-TOF, ICP-MS, UV–vis and photoluminescence spectra. To characterize the azo-imine ligands (HL¹–HL³), ¹H(¹³C)NMR methods were also used. To obtain the Cu²⁺ and Pt²⁺ complexes (POM-complexes) of the hybrid compounds (KL¹–KL³), the hybrid compounds and metal salts reacted in the C₂H₅OH solution. The POM-complexes were characterized by the spectroscopic and analytic methods, and then their photophysical, electrochemical and antimicrobial properties were investigated. In the UV–vis spectra of the POM based hybrid compounds KL¹–KL³, while ligand-centered π–π* transitions are in the range of 333–316 nm, the charge transfer transitions (CT) observed in the range of 458–453 nm. While the emission values of KL¹–KL³ compounds in DMF solution are in the range of 543–552 nm, the value of hybrid complexes shifted to the range of 570–697 nm. Antimicrobial activities of hybrid metal complexes were investigated and it was determined that all complexes showed activity against penicillium spp. Thermogravimetric analysis (TGA) studies were carried out to investigate the thermal behaviours of the metal complexes of the hybrid compounds.

Graphical abstract

Keywords: Keggin; Hybrid complexes; Electrochemical; Photophysical; Biological

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-024-03519-x

Chemical Papers 78 (10) 5969–5984 (2024)