Farklı Susuz Çözücülerde Schiff Bazı Ligandları ile Co(II) Kompleksleşmesinin Termodinamik Çalışmaları
Abstract
Bu çalışma, iki yeni Schiff bazı ligandı (L1 ve L2) ve bunların Co(II) iyonları ile susuz ortamda kompleksleşme davranışını araştırmaktadır. Ligand L1, o-hidroksiasetofenon ve salisaldehitin etilendiamin ile reaksiyonu sonucu, L2 ise 2,3-dihidroksibenzaldehit ve etilendiamin kullanılarak sentezlenmiştir. Co(II) komplekslerinin kararlılık sabitleri, 25°C ile 40°C arasında değişen sıcaklıklarda, etanol, asetonitril ve bu çözücülerin 1:1 karışımında iletkenlik ölçümleriyle belirlenmiştir. Sonuçlar, sıcaklığa bağlı olarak farklı kararlılık eğilimleri göstermiştir: L1 kompleksleri tüm çözücülerde artan sıcaklıkla kararlılığını azaltmış ve ekzotermik reaksiyonlar sergilemiştir, L2 kompleksleri ise asetonitril ve karışık çözücü ortamında endotermik reaksiyonları işaret eden farklı davranışlar göstermiştir. Çözücü ortamının kompleks kararlılığı üzerinde önemli etkileri olduğu görülmüş; en yüksek kararlılık asetonitrilde, ardından 1:1 çözücü karışımı ve etanolde gözlemlenmiştir. L2, daha fazla hidroksil grubunun Lewis bazlığını artırması nedeniyle L1'e kıyasla daha yüksek kararlılık sabitleri sergilemiştir, oysa L1'deki metil grubu, sterik engelleme yaratarak kararlılığı azaltmıştır. Termodinamik analiz, tüm reaksiyonlar için negatif ΔG° değerleri (-27,9 ila -32,1 kJ/mol) ile reaksiyonların kendiliğinden gerçekleştiğini ortaya koymuştur. Enthalpi değişimleri (ΔH°), ekzotermik reaksiyonlar için negatif (-27,6 ila -195 kJ/mol) ve endotermik reaksiyonlar için pozitif (7,37 ve 42,3 kJ/mol) değerler olarak bulunmuştur. Entropi değişimleri (ΔS°) ise moleküler organizasyon ve çözücü-ligand etkileşimlerindeki farklılıklara bağlı olarak değişim göstermiştir. Bu çalışma, susuz ortamda metal-ligand kompleksleşmesini etkileyen faktörlere dair önemli bilgiler sunarak kimya alanındaki çeşitli uygulamalara yönelik koordinasyon bileşiklerinin tasarımına katkıda bulunmaktadır.
Keywords
İletkenlik Ölçümü Schiff Bazları Kobalt Kompleksleri Kararlılık Sabitleri Susuz Çözücüler Termodinamik Parametreler
References
- R. Golbedaghi, F. Khajavi, Investigation of formation constant of complex of a new synthesized tripodal ligand with Cu²⁺ using rank annihilation factor analysis in surfactant media, Bull Chem Soc Ethiop, 28(1), 2014, 1-8.
- K.M. Elsherif, A. Zubi, A. Najar, H. Bin Ghashir, Determination of stoichiometry and stability constant of Cd(II) and Zn(II) complexes with pyrazole-based ligands in mixed solvent (EtOH-H2O), Sebha Univ J Pure Appl Sci, 21(2), 2022, 128-134.
- A.S. Alturiqi, E.S. Al-Farraj, M.M. Anazy, R.A. Ammar, Potentiometric determination of stability constants of binary and ternary complexes of L-tryptophan and anti-inflammatory drugs with Zn(II), Int J Electrochem Sci, 17, 2022, Article 220535.
- K.M. Elsherif, Q. Hadidan, K. Alkariwi, Spectrophotometric determination of Zn(II) and Cu(II) in analytical samples using murexide reagent, Prog Chem Biochem Res, 5(3), 2022, 229-238.
- S. Jadhav, M. Raia, R.K. Pardeshi, M. Farooqi, Determination of stability constant of metal-ligand equilibria with special reference to Schiff base and transition elements, Der Pharm Lett, 7(12), 2015, 316-320.
- Z.Y. Alzalouk, K.M.M. Elsherif, A. Zubi, R.M. Atiya, S. Al-Ddarwish, Metal chelates of copper and nickel with murexide in mixed isopropanol: Water solvent: Spectrophotometric study, Sci J Fac Sci Sirte Univ, 3(1), 2023, 9-17.
- K.M. Elsherif, A. Zubi, A. Najar, H. Bin Ghashir, Complexation of pyrazole-based ligands with Ag(I): Spectrophotometric studies in mixed solvents (EtOH-H2O), Arab J Chem Environ Res, 5(2), 2021, 138-146.
- A. Miličević, N. Raos, Stability prediction of Cu²⁺, Ni²⁺, and Zn²⁺ N-salicylidene-aminoacidato complexes by models based on connectivity index 3 χ₃ᵛ, Cent Eur J Chem, 12, 2014, 74-79.
- H.B. Shawish, K.M. Elsherif, A.M. Alkherraz, H.I. Shuwat, E.B. Al-Melah, Investigation of substitution reaction kinetics and thermodynamics between salen and [Cu(PDTC)2] complex, J Appl Organomet Chem, 4(1), 2024, 51-61.
- P.M. Mishra, V. Mishra, Physico–chemical study of transition metal complexes with Schiff’s base derived from naphthaldehyde and substituted aromatic amines, Orient J Chem, 32(5), 2016, 2745-55.
- M. Payehghadr, H.H. Qezelje, F.M. Dosangani, A. Amiri, S. Hosseini, M.N. Hesarlo, et al., Solution complexation reaction studies of a pyrazoloisoindol derivative ligand by some metal ions in acetonitrile solution, Orbital Electron J Chem, 10(6), 2018, 430–434.
- K.M. Elsherif, A. Zubi, H.B. Shawish, S.A. Abajja, E.B.M. Almelah, Complex formation of bis(salicylidene)ethylenediamine (Salen type ligand) with copper(II) ions in different solvents: Spectrophotometric and conductometric study, Int J New Chem, 7(1), 2020, 1–13.
- M. Payehghadr, S.E. Hashemi, Solvent effect on complexation reactions, J Inclusion Phenom Macrocycl Chem, 89(1-2), 2017, 253–271.
- K.M. Elsherif, A. Najar, H. Shuwat, Spectral study of 1,4-bis(3-(2-pyridyl)pyrazol-1-ylmethyl)benzene (PPB): UV-VIS absorption spectra investigation in single and binary solvents and spectrophotometric determination of the dissociation constant (pKb), Eurasian J Anal Chem, 12(1), 2017, 12(1):67–82.
- K.M. Elsherif, A. Zubi, H.B. Shawish, S.A. Abajja, E.B. Almelah, UV-VIS absorption spectral studies of N, N′-bis(salicylidene)ethylenediamine (Salen) in different solvents, Iraqi J Sci, 60(2), 2020, 204–210.
- S. Esmaielzadeh, G. Mashhadiagha, Formation constants and thermodynamic parameters of bivalent Co, Ni, Cu, and Zn complexes with Schiff base ligand: Experimental and DFT calculations, Bull Chem Soc Ethiop, 31(1), 2017, 159–170.
- B.N. Muthal, Synthesis of new Schiff bases and their transition metal complexes (CoII, NiII, CuII, & ZnII) and their characterization, stability constant, and microbial activities, Pharma Innov J, 6(3), 2017, 72–76.
- C. Boulechfar, H. Ferkous, A. Delimi, A. Djedouani, A. Kahlouche, A. Boublia, et al., Schiff bases and their metal complexes: A review on the history, synthesis, and applications, Inorg Chem Commun, 150, 2023, 110451.
- B.M. Kalshetty, S.S. Suvarnakhandi, R.C. Sheth, P.S. Hiremath, M.B. Kalashetti, Temperature effect on solution stability constants of metal complexes with Schiff bases derived from 5-aldehydosalicylic acid - aniline and its related compounds, Int J Appl Biol Pharm Technol, 2(2), 2011, 88–93.
- A. Farhan, Synthesis, identification of Co(II), Cu(II), and Ni(II) complexes with a Schiff base–azo ligand derived from imidazole derivatives, 4-aminoacetophenone, and 4-chloroaniline, and study of their physical properties and thermodynamic stabilities, J Univ Babylon Pure Appl Sci, 27(3), 2019, 406–419.
- L.K. Jha, Study of transition metal complex with Schiff's base derived from naphthaldehyde, Int J Adv Acad Stud, 4(1), 2022, 48-51.
- M. Nasir Uddin, D.A. Chowdhury, K. Hossain, Titanium(IV) complexes of unsymmetrical Schiff bases derived from ethylenediamine and o-hydroxyaldehyde/ketone and their anti-microbial evaluation, J Chin Chem Soc, 59(12), 2012, 1520-1527.
- C. Demetgül, M. Karakaplan, S. Serin, Synthesis, Characterization and Thermal Properties of Oligo-N,N′-bis (2,4-dihydroxybenzylidene) ethylenediamine and Its Cobalt (II) and Manganese (II) Complexes, Des Monomers Polym, 11(6), 2008, 565-579,
- M. Payehghadr, Synthesis and solution complexation studies of a new Schiff base ligand, J Phys Theor Chem Islamic Azad Univ Iran, 11(4), 2015, 165-175.
- S. Ahmadzadeh, A. Kassim, M. Rezayi, Y. Abdollahi, G.H. Rounaghi, A conductometric study of complexation reaction between meso-octamethylcalix[4]pyrrole with titanium cation in acetonitrile–ethanol binary mixtures, Int J Electrochem Sci, 6, 2011, 4749-4759.
- M. Rezayi, A. Kassim, S. Ahmadzadeh, N.A. Yusof, A. Naji, H. Abbastabar Ahangar, Conductometric determination of formation constants of tris(2-pyridyl)methylamine and titanium(III) in water-acetonitrile mixture, Int J Electrochem Sci, 6, 2011, 4378-4387.
- E.R. Enemo, T.E. Ezenwa, E.C. Nleonu, Determination of formation constants and thermodynamic parameters of chromium(III) ions with some ligands by conductometry, IOSR J Appl Chem, 12(10), 2019, 54-58.
- K.M. Elsherif, A. Zubi, Z.Y. Alzalouk, SA-S. Al-Darwish , Investigation of murexide-Zn(II) complexes in water-isopropanol mixtures: Spectroscopic analysis and stability studies, Sebha Univ J Pure Appl Sci, 23(1), 2024, 84-89.
- M. Joshaghani, M.B. Gholivand, F. Ahmadi, Spectrophotometric and conductometric study of complexation of salophen and some transition metal ions in nonaqueous polar solvents, Spectrochim Acta A Mol Biomol Spectrosc, 70(5), 2008, 1073-1078.
- S.O. Mohod, D.T. Tayad, D.T. Tayade , To determine the stability constant of Cu(II) with substituted thiocarbamidophenol by spectrophotometric measurements, Indo Am J Pharm Sci, 4(2), 2017, 245-247.
- P.R. Smirnov, Comparative characteristics of the nearest environment structures of metal ions in water and acetonitrile (A review), Russ J Gen Chem, 93(3), 2023, 575–585.
- K.M. Elsherif, A. Zubi, A. Najar, E. Bazina, Complexation of 1,4-bis(3-(2-pyridyl)pyrazol-1-ylmethyl)benzene (1,4-PPB) with Cu(II), Co(II), and Ni(II): Spectrophotometric studies in mixed solvent (EtOH-H2O), To Chem, 1(2), 2018, 214-223.
- SA-S. Al-Darwish, K.M. Elsherif, A. Zubi, Z.Y. Alzalouk, R.M. Atiya, Study of absorption spectrum of murexide complex with cobalt ion in a water and 2-propanol solvent mixture, Al-Mukhtar J Sci, 38(2), 2023, 199-208.
- S. Di Bella, Lewis acidic zinc(II) salen-type Schiff-base complexes: Sensing properties and responsive nanostructures, Dalton Trans, 50, 2021, 6050-6063.
- N.O. Tapabashi, A.B. Dakeel, N.O. Tapabashi, Study of the kinetics and thermodynamic parameters of Schiff bases derived from 4-aminoantipyrin, Cent Asian J Med Nat Sci, 5(1), 2024, 573-588.
Thermodynamic Studies of Co(II) Complexation with Schiff Base Ligands in Different Nonaqueous Solvents
Abstract
This study investigates the synthesis and characterization of two novel Schiff base ligands, L1 and L2, and their complexation behavior with Co(II) ions in non-aqueous media. Ligand L1 was synthesized using o-hydroxyacetophenone and salicylaldehyde with ethylenediamine, while L2 was prepared with 2,3-dihydroxybenzaldehyde and ethylenediamine. Conductometric measurements in ethanol, acetonitrile, and a 1:1 mixture of these solvents at temperatures ranging from 25°C to 40°C determined the stability constants of the Co(II) complexes. Results showed distinct temperature-dependent stability trends: L1 complexes decreased in stability with increasing temperature in all solvents, indicating exothermic reactions, while L2 complexes showed varied behavior, suggesting endothermic reactions in acetonitrile and the mixed solvent. The solvent environment significantly influenced complex stability, with acetonitrile showing the highest stability, followed by the 1:1 solvent mixture and ethanol. L2 exhibited higher stability constants than L1, attributed to additional hydroxyl groups in L2 enhancing Lewis basicity, while the methyl group in L1 caused steric hindrance, reducing stability. Thermodynamic analysis revealed negative ΔG° values (-27.9 to -32.1 kJ/mol) for all reactions, indicating spontaneity. Enthalpy changes (ΔH°) varied, with negative values (-27.6 to -195 kJ/mol) for exothermic and positive values (7.37 and 42.3 kJ/mol) for endothermic reactions. Entropy changes (ΔS°) varied, reflecting differences in molecular organization and solvent-ligand interactions. This study provides insights into factors affecting metal-ligand complexation in non-aqueous environments, with implications for designing coordination compounds for various applications in chemistry
Keywords
Conductometry Schiff Bases Cobalt Complexes Stability Constants Nonaqueous Solutions Thermodynamic Parameters
References
- R. Golbedaghi, F. Khajavi, Investigation of formation constant of complex of a new synthesized tripodal ligand with Cu²⁺ using rank annihilation factor analysis in surfactant media, Bull Chem Soc Ethiop, 28(1), 2014, 1-8.
- K.M. Elsherif, A. Zubi, A. Najar, H. Bin Ghashir, Determination of stoichiometry and stability constant of Cd(II) and Zn(II) complexes with pyrazole-based ligands in mixed solvent (EtOH-H2O), Sebha Univ J Pure Appl Sci, 21(2), 2022, 128-134.
- A.S. Alturiqi, E.S. Al-Farraj, M.M. Anazy, R.A. Ammar, Potentiometric determination of stability constants of binary and ternary complexes of L-tryptophan and anti-inflammatory drugs with Zn(II), Int J Electrochem Sci, 17, 2022, Article 220535.
- K.M. Elsherif, Q. Hadidan, K. Alkariwi, Spectrophotometric determination of Zn(II) and Cu(II) in analytical samples using murexide reagent, Prog Chem Biochem Res, 5(3), 2022, 229-238.
- S. Jadhav, M. Raia, R.K. Pardeshi, M. Farooqi, Determination of stability constant of metal-ligand equilibria with special reference to Schiff base and transition elements, Der Pharm Lett, 7(12), 2015, 316-320.
- Z.Y. Alzalouk, K.M.M. Elsherif, A. Zubi, R.M. Atiya, S. Al-Ddarwish, Metal chelates of copper and nickel with murexide in mixed isopropanol: Water solvent: Spectrophotometric study, Sci J Fac Sci Sirte Univ, 3(1), 2023, 9-17.
- K.M. Elsherif, A. Zubi, A. Najar, H. Bin Ghashir, Complexation of pyrazole-based ligands with Ag(I): Spectrophotometric studies in mixed solvents (EtOH-H2O), Arab J Chem Environ Res, 5(2), 2021, 138-146.
- A. Miličević, N. Raos, Stability prediction of Cu²⁺, Ni²⁺, and Zn²⁺ N-salicylidene-aminoacidato complexes by models based on connectivity index 3 χ₃ᵛ, Cent Eur J Chem, 12, 2014, 74-79.
- H.B. Shawish, K.M. Elsherif, A.M. Alkherraz, H.I. Shuwat, E.B. Al-Melah, Investigation of substitution reaction kinetics and thermodynamics between salen and [Cu(PDTC)2] complex, J Appl Organomet Chem, 4(1), 2024, 51-61.
- P.M. Mishra, V. Mishra, Physico–chemical study of transition metal complexes with Schiff’s base derived from naphthaldehyde and substituted aromatic amines, Orient J Chem, 32(5), 2016, 2745-55.
- M. Payehghadr, H.H. Qezelje, F.M. Dosangani, A. Amiri, S. Hosseini, M.N. Hesarlo, et al., Solution complexation reaction studies of a pyrazoloisoindol derivative ligand by some metal ions in acetonitrile solution, Orbital Electron J Chem, 10(6), 2018, 430–434.
- K.M. Elsherif, A. Zubi, H.B. Shawish, S.A. Abajja, E.B.M. Almelah, Complex formation of bis(salicylidene)ethylenediamine (Salen type ligand) with copper(II) ions in different solvents: Spectrophotometric and conductometric study, Int J New Chem, 7(1), 2020, 1–13.
- M. Payehghadr, S.E. Hashemi, Solvent effect on complexation reactions, J Inclusion Phenom Macrocycl Chem, 89(1-2), 2017, 253–271.
- K.M. Elsherif, A. Najar, H. Shuwat, Spectral study of 1,4-bis(3-(2-pyridyl)pyrazol-1-ylmethyl)benzene (PPB): UV-VIS absorption spectra investigation in single and binary solvents and spectrophotometric determination of the dissociation constant (pKb), Eurasian J Anal Chem, 12(1), 2017, 12(1):67–82.
- K.M. Elsherif, A. Zubi, H.B. Shawish, S.A. Abajja, E.B. Almelah, UV-VIS absorption spectral studies of N, N′-bis(salicylidene)ethylenediamine (Salen) in different solvents, Iraqi J Sci, 60(2), 2020, 204–210.
- S. Esmaielzadeh, G. Mashhadiagha, Formation constants and thermodynamic parameters of bivalent Co, Ni, Cu, and Zn complexes with Schiff base ligand: Experimental and DFT calculations, Bull Chem Soc Ethiop, 31(1), 2017, 159–170.
- B.N. Muthal, Synthesis of new Schiff bases and their transition metal complexes (CoII, NiII, CuII, & ZnII) and their characterization, stability constant, and microbial activities, Pharma Innov J, 6(3), 2017, 72–76.
- C. Boulechfar, H. Ferkous, A. Delimi, A. Djedouani, A. Kahlouche, A. Boublia, et al., Schiff bases and their metal complexes: A review on the history, synthesis, and applications, Inorg Chem Commun, 150, 2023, 110451.
- B.M. Kalshetty, S.S. Suvarnakhandi, R.C. Sheth, P.S. Hiremath, M.B. Kalashetti, Temperature effect on solution stability constants of metal complexes with Schiff bases derived from 5-aldehydosalicylic acid - aniline and its related compounds, Int J Appl Biol Pharm Technol, 2(2), 2011, 88–93.
- A. Farhan, Synthesis, identification of Co(II), Cu(II), and Ni(II) complexes with a Schiff base–azo ligand derived from imidazole derivatives, 4-aminoacetophenone, and 4-chloroaniline, and study of their physical properties and thermodynamic stabilities, J Univ Babylon Pure Appl Sci, 27(3), 2019, 406–419.
- L.K. Jha, Study of transition metal complex with Schiff's base derived from naphthaldehyde, Int J Adv Acad Stud, 4(1), 2022, 48-51.
- M. Nasir Uddin, D.A. Chowdhury, K. Hossain, Titanium(IV) complexes of unsymmetrical Schiff bases derived from ethylenediamine and o-hydroxyaldehyde/ketone and their anti-microbial evaluation, J Chin Chem Soc, 59(12), 2012, 1520-1527.
- C. Demetgül, M. Karakaplan, S. Serin, Synthesis, Characterization and Thermal Properties of Oligo-N,N′-bis (2,4-dihydroxybenzylidene) ethylenediamine and Its Cobalt (II) and Manganese (II) Complexes, Des Monomers Polym, 11(6), 2008, 565-579,
- M. Payehghadr, Synthesis and solution complexation studies of a new Schiff base ligand, J Phys Theor Chem Islamic Azad Univ Iran, 11(4), 2015, 165-175.
- S. Ahmadzadeh, A. Kassim, M. Rezayi, Y. Abdollahi, G.H. Rounaghi, A conductometric study of complexation reaction between meso-octamethylcalix[4]pyrrole with titanium cation in acetonitrile–ethanol binary mixtures, Int J Electrochem Sci, 6, 2011, 4749-4759.
- M. Rezayi, A. Kassim, S. Ahmadzadeh, N.A. Yusof, A. Naji, H. Abbastabar Ahangar, Conductometric determination of formation constants of tris(2-pyridyl)methylamine and titanium(III) in water-acetonitrile mixture, Int J Electrochem Sci, 6, 2011, 4378-4387.
- E.R. Enemo, T.E. Ezenwa, E.C. Nleonu, Determination of formation constants and thermodynamic parameters of chromium(III) ions with some ligands by conductometry, IOSR J Appl Chem, 12(10), 2019, 54-58.
- K.M. Elsherif, A. Zubi, Z.Y. Alzalouk, SA-S. Al-Darwish , Investigation of murexide-Zn(II) complexes in water-isopropanol mixtures: Spectroscopic analysis and stability studies, Sebha Univ J Pure Appl Sci, 23(1), 2024, 84-89.
- M. Joshaghani, M.B. Gholivand, F. Ahmadi, Spectrophotometric and conductometric study of complexation of salophen and some transition metal ions in nonaqueous polar solvents, Spectrochim Acta A Mol Biomol Spectrosc, 70(5), 2008, 1073-1078.
- S.O. Mohod, D.T. Tayad, D.T. Tayade , To determine the stability constant of Cu(II) with substituted thiocarbamidophenol by spectrophotometric measurements, Indo Am J Pharm Sci, 4(2), 2017, 245-247.
- P.R. Smirnov, Comparative characteristics of the nearest environment structures of metal ions in water and acetonitrile (A review), Russ J Gen Chem, 93(3), 2023, 575–585.
- K.M. Elsherif, A. Zubi, A. Najar, E. Bazina, Complexation of 1,4-bis(3-(2-pyridyl)pyrazol-1-ylmethyl)benzene (1,4-PPB) with Cu(II), Co(II), and Ni(II): Spectrophotometric studies in mixed solvent (EtOH-H2O), To Chem, 1(2), 2018, 214-223.
- SA-S. Al-Darwish, K.M. Elsherif, A. Zubi, Z.Y. Alzalouk, R.M. Atiya, Study of absorption spectrum of murexide complex with cobalt ion in a water and 2-propanol solvent mixture, Al-Mukhtar J Sci, 38(2), 2023, 199-208.
- S. Di Bella, Lewis acidic zinc(II) salen-type Schiff-base complexes: Sensing properties and responsive nanostructures, Dalton Trans, 50, 2021, 6050-6063.
- N.O. Tapabashi, A.B. Dakeel, N.O. Tapabashi, Study of the kinetics and thermodynamic parameters of Schiff bases derived from 4-aminoantipyrin, Cent Asian J Med Nat Sci, 5(1), 2024, 573-588.
Details
| Primary Language | English |
|---|---|
| Subjects | Electroanalytical Chemistry, Analytical Chemistry (Other) |
| Journal Section | Research Articles |
| Authors | |
| Publication Date | May 31, 2025 |
| Submission Date | December 24, 2024 |
| Acceptance Date | February 7, 2025 |
| Published in Issue | Year 2025 Volume: 7 Issue: 2 |
