Synthesis and Characterization of Thiophene Cyclic Schiff Base Ligand and Metal Ion Complexes

Yıl 2025, Cilt: 8 Sayı: 6, 1864 - 1873, 15.11.2025

Ali Çapan , Abdülhamid Elhac Hasan , Mehmet Sönmez

https://doi.org/10.34248/bsengineering.1725400

Öz

In this study, a new Schiff base ligand (L) containing a thiophene ring was synthesized via the reaction of thiophene-2,5-dicarbaldehyde with 5-amino-1,3,4-thiadiazole-2-thiol. The structure of the ligand was elucidated using elemental analysis, FT-IR, NMR, and UV-Vis spectroscopy. The ligand (L) reacted with metal acetate salts [M(CH₃COO)₂; M = Cu, Co, Ni] in a 1:1 molar ratio to form metal complexes with the general formula [ML(CH₃COO)₂]•nH₂O (n = 2, 3). Structural characterization of the metal complexes was performed using elemental analysis, FT-IR, UV-Vis, TGA/DTA, electrolytic conductivity, and magnetic susceptibility measurements. Based on the obtained data, it was proposed that the Cu(II), Co(II), and Ni(II) complexes adopt a tetrahedral geometry. Moreover, the molar conductivities of the complexes were found to be in the range of 1.5–2.9 μS•cm⁻¹, indicating their non-electrolytic nature.

Anahtar Kelimeler

Thiophene , Thiadiazole , Schiff base , Metal complex , Characterization

Etik Beyan

Ethics committee approval was not required for this study since there was no study on animals or humans.

Proje Numarası

FEF.YLT.23.03

Teşekkür

This article is derived from the master's thesis research project numbered FEF.YLT.23.03. We would like to thank the Scientific Research Projects Unit of Gaziantep University for their support.

Kaynakça

• Abdel Aziz AA, Seda SH. 2017. Synthesis, structural features and biochemical activity assessment of N,N′‐bis‐(2‐mercaptophenylimine)‐2,5‐thiophenedicarboxaldehyde Schiff base and its Co(II), Ni(II), Cu(II) and Zn(II) complexes. Appl Organomet Chem, 31(12): 3879. https://doi.org/10.1002/aoc.3879
• Abd-El-Aziz A, Li Z, Zhang X, Elnagdy S, Mansour MS, ElSherif A, Ma N, Abd-El-Aziz AS. 2025. Advances in coordination chemistry of Schiff base complexes: A journey from nanoarchitectonic design to biomedical applications. Top Curr Chem, 383(1): 1-102. https://doi.org/10.1007/s41061-025-00489-w
• Babu KA, Singhvi I, Ravindra N, Shaik AB. 2020. Antimicrobial and antitubercular evaluation of some new 5-amino-1,3,4-thiadiazole-2-thiol derived Schiff Bases. Rev Roum Chim, 65(9): 771-776. https://doi.org/10.33224/rrch.2020.65.9.01
• Bandi KR, Singh AK, Upadhyay A. 2014. Electroanalytical and naked eye determination of Cu²⁺ ion in various environmental samples using 5-amino-1,3,4-thiadiazole-2-thiol based Schiff bases. Mater Sci Eng C Mater Biol Appl, 34: 149-157. https://doi.org/10.1016/j.msec.2013.09.006
• Begum M, Puttaveerappa D, Marisamy VH, Dharmappa RN. 2022. Synthesis, characterization and larvicidal activity of Schiff base ligand 5-(((5-mercapto-1,3,4-thiadiazol-2-yl)imino)methyl)-2-methoxyphenol and its metal(II) complexes. SSRN. 4274113. https://doi.org/10.2139/ssrn.4274113
• Beytur M, Akyıldırım O, Aktaş Yokuş Ö. 2019. Synthesis, characterization and DFT calculations of 5-Mercapto-2-(3-methyl-thiophen-2-yl-methylidenamino)-1,3,4-thiadiazole compound. J Suleyman Demirel Univ Inst Sci, 23(2): 411-418. https://doi.org/10.19113/sdufenbed.500767
• Bingöl M, Turan N. 2020. Schiff base and metal(II) complexes containing thiophene-3-carboxylate: Synthesis, characterization and antioxidant activities. J Mol Struct, 1205: 127542. https://doi.org/10.1016/j.molstruc.2019.127542
• Capan A, Uruş S, Sönmez M. 2018. Ru (III), Cr (III), Fe (III) complexes of Schiff base ligands bearing phenoxy Groups: Application as catalysts in the synthesis of vitamin K3. J Saudi Chem Soc, 22(6): 757-766. https://doi.org/10.1016/j.jscs.2017.12.007
• Chandra S, Gautam S, Rajor HK, Bhatia R. 2015. Syntheses, spectroscopic characterization, thermal study, molecular modeling, and biological evaluation of novel Schiff’s base benzil bis(5-amino-1,3,4-thiadiazole-2-thiol) with Ni(II), and Cu(II) metal complexes. Spectrochim Acta A Mol Biomol Spectrosc, 137: 749-760. https://doi.org/10.1016/j.saa.2014.08.046
• Dhanapal P, Manju SL. 2024. Thiophene appended Schiff base probe for selective ‘turn-on’ response for copper(II) ion and their applications in live cell imaging. Synth Met, 309: 117752. https://doi.org/10.1016/j.synthmet.2024.117752
• Kumar M, Singh AK, Singh AK, Yadav RK, Singh S, Singh AP, Chauhan A. 2023. Recent advances in 3d-block metal complexes with bi, tri, and tetradentate Schiff base ligands derived from salicylaldehyde and its derivatives: Synthesis, characterization and applications. Coord Chem Rev, 488: 215176. https://doi.org/10.1016/j.ccr.2023.215176
• Miroslaw B. 2020. Homo- and hetero-oligonuclear complexes of platinum group metals (PGM) coordinated by imine Schiff base ligands. Int J Mol Sci, 21(10): 3493. https://doi.org/10.3390/ijms21103493
• Mishra G, Dwivedi PK, Verma N, Srivastava S, Singh AK, Chaturvedi D. 2023. p-TSA-promoted efficient synthesis of some new thiophene hybridized thiadiazolyl Schiff bases as antibacterial agents. Indian J Heterocycl Chem, 33(03): 361-368. https://doi.org/10.59467/IJHC.2023.33.361
• Pandey A, Rajavel R, Chandraker S, Dash D. 2012. Synthesis of Schiff bases of 2-amino-5-aryl-1,3,4-thiadiazole and its analgesic, anti-inflammatory and anti-bacterial activity. J Chem, 9(4): 2524-2531. https://doi.org/10.1155/2012/145028
• Pandey AK, Baboo V, Mishra VN, Singh VK, Dwivedi A. 2022. Comparative Study of Molecular Docking, Structural, Electronic, Vibrational Spectra and Fukui Function Studies of Thiadiazole Containing Schiff Base – A Complete Density Functional Study. Polycycl Aromat Compd 42: 13–39. https://doi.org/10.1080/10406638.2020.1712440
• Pervaiz M, Quratulain R, Ejaz A, Shain M, Saeed Z, Nasir S, Khan R, Ashraf AS, Younas U. 2023. Thiosemicarbazides, 1,3,4 thiadiazole Schiff base derivatives of transition metal complexes as antimicrobial agents. Inorg Chem Commun, 160: 111856. https://doi.org/10.1016/j.inoche.2023.111856
• Radha VP, Prabakaran M. 2022. Novel thiadiazole‐derived Schiff base ligand and its transition metal complexes: Thermal behaviour, theoretical study, chemo‐sensor, antimicrobial, antidiabetic and anticancer activity. App Org Chem, 36(11): 6872. https://doi.org/10.1002/aoc.6872
• Rajimon KJ, Alzahrani AY, Aazam ES, Abbas BM, Govindarajan P, Thomas R. 2024. Unveiling the multifaceted potential of (E)-N-(4-chlorophenyl)-1-(thiophen-2-yl)methanimine. J Mol Struct, 1302: 137428. https://doi.org/10.1016/j.molstruc.2023.137428
• Reeja J, Thomas KJ, Ragi K, Binsi MP. 2022. Screening of two sulphur-containing Schiff’s bases corrosion inhibition properties on CS: Gravimetric, electrochemical and quantum chemical studies. Port Electrochim Acta, 40: 223-241. https://doi.org/10.4152/pea.2022400401
• Rezki N, Al-Yahyawi A, Bardaweel S, Al-Blewi F, Aouad M. 2015. Synthesis of Novel 2,5-Disubstituted1,3,4-thiadiazoles Clubbed 1,2,4-Triazole, 1,3,4-Thiadiazole, 1,3,4-Oxadiazole and/or Schiff Base as Potential Antimicrobial and Antiproliferative Agents. Molecules, 20: 16048-16067. https://doi.org/10.3390/molecules200916048
• Saritha TJ, Metilda, P. 2021. Synthesis, spectroscopic characterization and biological applications of some novel Schiff base transition metal(II) complexes derived from curcumin moiety. J Saudi Chem Soc, 25(6): 101245. https://doi.org/10.1016/j.jscs.2021.101245
• Shaalan N, Khalaf WM, Mahdi S. 2022. Preparation and Characterization of New Tetra-Dentate; Schiff Base with Some of Metal Ions Complexes. Indones J Chem, 22 (1): 62-71. https://doi.org/10.22146/ijc.66118
• Shalinee, Kumar S. 2024. Eco-friendly synthesis, characterization, and antimicrobial evaluation of transition metal (II) complexes with Thiophene-Derived Tridentate (S N N Donor) Heterocyclic Schiff Base Ligand. Int Res J Pure Appl Chem, 25(6): 28-40. https://doi.org/10.9734/irjpac/2024/v25i6883
• Soliman AMM, Abd El Aleem Ali Ali El-Remaily M, Kamel MS, El-Araby A, Shokr EK. 2025. Synthesis and optical properties of Schiff base derivatives of thieno[2,3-b]thiophene-2,5-dicarbohydrazide. Sci Rep, 15(1): 1611. https://doi.org/10.1038/s41598-024-83994-0
• Soroceanu A, Bargan A. 2022. Advanced and biomedical applications of Schiff-base ligands and their metal complexes: A review. Crystals, 12(10): 1436. https://doi.org/10.3390/cryst12101436
• Suganya S, Velmathi S, Mubarak Ali D. 2014. Highly selective chemosensor for nanomolar detection of Cu²⁺ ion by fluorescent turn-on response and its application in living cells. Dyes Pigm, 104: 116-122. https://doi.org/10.1016/j.dyepig.2014.01.001
• Süleymanoğlu N, Demir EE, Direkel Ş, Ünver Y. 2020. Theoretical study and antimicrobial activities of New Schiff base derivatives with thiophene. J Mol Struct, 1218: 128522. https://doi.org/10.1016/j.molstruc.2020.128522
• Warad I, Bsharat O, Tabti S, Djedouani A, Al-Nuri M, Al-Zaqri N, Kumara K, Lokanath NK, Amereih S, Abu-Reidah IM. 2019. Crystal interactions, computational, spectral and thermal analysis of Schiff base ligand derived from thiophene. J Mol Struct, 1185: 290-299. https://doi.org/10.1016/j.molstruc.2019.02.109
• Xiong C, Li Y, Wang G, Fang L, Zhou S, Yao C, Chen Q, Zheng X, Qi D, Fu Y, Zhu Y. 2015. Selective removal of Hg(II) with polyacrylonitrile-2-amino-1,3,4-thiadiazole chelating resin. Chem Eng J, 259: 257-265. https://doi.org/10.1016/j.cej.2014.07.114
• Zhang R, Wang Q, Li Q, Ma C. 2009. Syntheses and characterization of triorganotin(IV) complexes of Schiff base derived from 4-amino-5-phenyl-1,2,4-triazole and 5-amino-1,3,4-thiadiazole. Inorg Chim Acta, 362: 2762-2769. https://doi.org/10.1016/j.ica.2008.12.017