1
|
Gajecki L, Sawicka B, Berg DJ, Oliver AG. Synthesis and Magnetic Studies of Two Neutral, Bis-Ligand Fe(II) Complexes Containing Carbazole- Bis(tetrazole) Ligands. Inorg Chem 2023. [PMID: 37478316 DOI: 10.1021/acs.inorgchem.3c01167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/23/2023]
Abstract
Previously reported carbazole-bis(tetrazole) (CzTR) ligands (where R = iPr and CH2-2,4,6-C6H2Me3) were used to synthesize air-stable, six-coordinate, octahedral bis-ligand Fe(II) complexes (CzTR)2Fe. The synthesis and characterization of these complexes using 1H nuclear magnetic resonance (NMR), X-ray crystallography, Mössbauer spectroscopy, and density functional theory (DFT) calculations are reported. Analysis of the magnetic properties revealed that the isopropyl derivative displays thermally induced spin crossover (SCO) over a temperature range of 150-350 K. This transition appears as an abrupt two-step transition in the solid state but simplifies to a smooth one-step transition in solution. The two-step transition in the solid state has been postulated to be due to lattice and solvation effects. In contrast, the slightly bulkier substituted CH2-2,4,6-C6H2Me3 (CH2Mes) Fe complex displays dramatically different magnetic behavior with no SCO and magnetic data suggesting low-spin Fe(II) with a possible TIP contribution. DFT calculations support the postulate that the change in magnetic behavior is primarily due to the nature of the ligand substituents.
Collapse
Affiliation(s)
- Leah Gajecki
- Department of Chemistry, University of Victoria, P.O. Box 3065, Victoria, British Columbia, Canada V8W 3V6
| | - Barbara Sawicka
- Department of Mechanical Engineering, University of Victoria, P.O. Box 1700 STN CSC, Victoria, British Columbia, Canada V8W 2Y2
| | - David J Berg
- Department of Chemistry, University of Victoria, P.O. Box 3065, Victoria, British Columbia, Canada V8W 3V6
| | - Allen G Oliver
- Department of Chemistry & Biochemistry, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, Indiana 46556, United States
| |
Collapse
|
2
|
Parmar SV, Avasare V, Pal S. Unraveling the Effect of Aromatic Groups in Mn(I)NNN Pincer Complexes on Carbon Dioxide Activation Using Density Functional Study. Front Chem 2021; 9:778718. [PMID: 34869226 PMCID: PMC8639700 DOI: 10.3389/fchem.2021.778718] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 10/11/2021] [Indexed: 11/13/2022] Open
Abstract
Carbon dioxide utilization is necessary to reduce carbon footprint and also to synthesize value-added chemicals. The transition metal pincer complexes are attractive catalysts for the hydrogenation of carbon dioxide to formic acid. There is a need to understand the factors affecting the catalytic performance of these pincer complexes through a structure-activity relationship study using computational methods. It is a well-established fact that aromatic functionalities offer stability and selectivity to transition metal catalysts. However, their impact on the performance of the catalysts is lesser known in the case of metal pincer complexes. Hence, it is necessary to investigate the catalytic performance of Mn(I)NNN pincer complexes with variably activated aromatic functionalities. In this context, 15 catalysts are designed by placing different types of aromatic rings at the pincer carbons and two terminal nitrogen of Mn(I)NNN pincer complexes. A benzene moiety, placed at C2-C3 carbons of Mn(I)NNN pincer complex with identical aromatic groups at the terminal nitrogen, is found to be most efficient toward CO2 hydrogenation than the rest of the catalysts. On the other hand, when N,N-dimethyl aniline is placed at C2-C3 carbons of Mn(I)NNN pincer complexes, then the catalytic performance is significantly decreased. Thus, the present study unravels the impact of aromatic groups in Mn(I)NNN pincer complexes toward the catalytic hydrogenation of carbon dioxide.
Collapse
Affiliation(s)
| | - Vidya Avasare
- Department of Chemistry, Sir Parashurambhau College, Pune, India.,Department of Chemistry, Ashoka University, Sonipat, India
| | - Sourav Pal
- Department of Chemistry, Ashoka University, Sonipat, India.,Indian Institute of Science Education and Research, Kolkata, India
| |
Collapse
|
3
|
Anwar MU, Al-Harrasi A, Rawson JM. Structures, properties and applications of Cu(II) complexes with tridentate donor ligands. Dalton Trans 2021; 50:5099-5108. [PMID: 33881088 DOI: 10.1039/d1dt00483b] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Tridentate ligands offer theree donor atoms to coordinate to metal ions. The remaining vacant coordination sites on the metal ions provided opportunities to implement additional co-ligands to generate complexes with desired properties. Herein we discuss selected examples of Cu(ii) complexes with tridentate ligands utilizing combinations of N, O, S, and Se donors, focusing on effects of ligand flexibility/rigidity on their coordination modes, properties and applications.
Collapse
Affiliation(s)
- Muhammad Usman Anwar
- Natural and Medical Sciences Research Centre, University of Nizwa, Birkat Almouz 616, Oman.
| | - Ahmed Al-Harrasi
- Natural and Medical Sciences Research Centre, University of Nizwa, Birkat Almouz 616, Oman.
| | - Jeremy M Rawson
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Ave, Windsor, ON N9B3P4, Canada.
| |
Collapse
|
4
|
Samanta S, Zheng C, Gajecki L, Berg DJ, Oliver AG, Crosby T, Godin L, Sandhu J. Carbazolyl- bis(triazole) and Carbazolyl- bis(tetrazole) Complexes of Palladium(II) and Platinum(II). J COORD CHEM 2021. [DOI: 10.1080/00958972.2021.1882674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Samya Samanta
- Department of Chemistry, University of Victoria, Victoria, BC, Canada
| | - Cameron Zheng
- Department of Chemistry, University of Victoria, Victoria, BC, Canada
| | - Leah Gajecki
- Department of Chemistry, University of Victoria, Victoria, BC, Canada
| | - David J. Berg
- Department of Chemistry, University of Victoria, Victoria, BC, Canada
| | - Allen G. Oliver
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Tristan Crosby
- Department of Chemistry, University of Victoria, Victoria, BC, Canada
| | - Logan Godin
- Department of Chemistry, University of Victoria, Victoria, BC, Canada
| | - Jaylene Sandhu
- Department of Chemistry, University of Victoria, Victoria, BC, Canada
| |
Collapse
|
5
|
Chisholm DT, Hayes PG. Synthesis and characterization of group 13 dichloride (M = Ga, In), dimethyl (M = Al) and cationic methyl aluminum complexes supported by monoanionic NNN-pincer ligands. NEW J CHEM 2021. [DOI: 10.1039/d1nj01064f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of monoanionic NNN-pincer ligands effectively stabilize five-coordinate gallium and indium dichloride complexes, as well as neutral dimethyl aluminum species, and organometallic cations thereof.
Collapse
Affiliation(s)
- Desmond T. Chisholm
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive, Lethbridge, AB, Canada T1K 3M4
| | - Paul G. Hayes
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive, Lethbridge, AB, Canada T1K 3M4
| |
Collapse
|
6
|
Singh A, Raj P, Singh A, Dubowski JJ, Kaur N, Singh N. Metal-Organocatalyst for Detoxification of Phosphorothioate Pesticides: Demonstration of Acetylcholine Esterase Activity. Inorg Chem 2019; 58:9773-9784. [PMID: 31318533 DOI: 10.1021/acs.inorgchem.9b00770] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In recent years, transition metal complexes have been developed for catalytical degradation of a phosphate ester bond, particularly in RNA and DNA; however, less consideration has been given for development of complexes for the degradation of a phosphorothioate bond, as they are the foremost used pesticides in the environment and are toxic to human beings. In this context, we have developed copper complexes of benzimidazolium based ligands for catalytical degradation of a series of organophosphates (parathion, paraoxon, methyl-parathion) at ambient conditions. The copper complexes (assigned as N1-N3) were characterized using single X-ray crystallography which revealed that all three complexes are mononuclear and distorted square planner in geometry. Further, the solution state studies of the prepared complexes were carried out using UV-visible absorption, fluorescence spectroscopy, and cyclic voltametry. The complexes N1 and N2 have benzimidazolium ionic liquid as base attached with two 2-mercapto-benzimidazole pods, whereas complex N3 contains a nonionic ligand. The synthesized copper complexes were evaluated for their catalytic activity for degradation of organophosphates. It is interesting that the complex containing the ionic ligand efficiently degrades phosphorothioate pesticides, whereas complex N3 was not found to be appropriate for degradation due to a weaker conversion rate. The organophosphate degradation studies were monitored by recording absorbance spectra of parathion in the presence of catalyst, i.e., copper complexes with respect to time. The parathion was hydrolyzed into para-nitrophenol and diethyl thiophosphate. Moreover, to analyze the inhibition activity of the pesticides toward acetylcholine esterase enzyme in the presence of prepared metal complexes, Ellman's assay was performed and revealed that, within 20 min, the inhibition of acetylcholine esterase enzyme decreases by up to 13%.
Collapse
Affiliation(s)
- Amanpreet Singh
- Department of Chemistry , Indian Institute of Technology Ropar , Punjab 140001 , India
| | - Pushap Raj
- Department of Chemistry , Indian Institute of Technology Ropar , Punjab 140001 , India
| | - Ajnesh Singh
- Department of Applied Sciences and Humanities , Jawaharlal Nehru Govt. Engineering College , Sundernagar , Mandi (H.P.) , 175018 , India
| | - Jan J Dubowski
- Laboratory for Quantum Semiconductors and Photo-based Biotechnology, Interdisciplinary Institute for Technological Innovation (3IT), CNRS UMI-3463, Department of Electrical and Computer Engineering , Universite de Sherbrooke , 3000 Boulevard de l'Université , Sherbrooke , QC J1K 0A5 , Canada
| | - Navneet Kaur
- Department of Chemistry , Panjab University , Chandigarh , 160014 , India
| | - Narinder Singh
- Department of Chemistry , Indian Institute of Technology Ropar , Punjab 140001 , India
| |
Collapse
|
7
|
Lawrence MA, Green KA, Nelson PN, Lorraine SC. Review: Pincer ligands—Tunable, versatile and applicable. Polyhedron 2018. [DOI: 10.1016/j.poly.2017.08.017] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
|