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Microwave-Assisted Synthesis: Can Transition Metal Complexes Take Advantage of This “Green” Method? Molecules 2022; 27:molecules27134249. [PMID: 35807493 PMCID: PMC9267986 DOI: 10.3390/molecules27134249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Revised: 06/27/2022] [Accepted: 06/28/2022] [Indexed: 01/27/2023] Open
Abstract
Microwave-assisted synthesis is considered environmental-friendly and, therefore, in agreement with the principles of green chemistry. This form of energy has been employed extensively and successfully in organic synthesis also in the case of metal-catalyzed synthetic procedures. However, it has been less widely exploited in the synthesis of metal complexes. As microwave irradiation has been proving its utility as both a time-saving procedure and an alternative way to carry on tricky transformations, its use can help inorganic chemists, too. This review focuses on the use of microwave irradiation in the preparation of transition metal complexes and organometallic compounds and also includes new, unpublished results. The syntheses of the compounds are described following the group of the periodic table to which the contained metal belongs. A general overview of the results from over 150 papers points out that microwaves can be a useful synthetic tool for inorganic chemists, reducing dramatically the reaction times with respect to traditional heating. This is often accompanied by a more limited risk of decomposition of reagents or products by an increase in yield, purity, and (sometimes) selectivity. In any case, thermal control is operative, whereas nonthermal or specific microwave effects seem to be absent.
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Beillard A, Bantreil X, Métro TX, Martinez J, Lamaty F. Alternative Technologies That Facilitate Access to Discrete Metal Complexes. Chem Rev 2019; 119:7529-7609. [PMID: 31059243 DOI: 10.1021/acs.chemrev.8b00479] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Organometallic complexes: these two words jump to the mind of the chemist and are directly associated with their utility in catalysis or as a pharmaceutical. Nevertheless, to be able to use them, it is necessary to synthesize them, and it is not always a small matter. Typically, synthesis is via solution chemistry, using a round-bottom flask and a magnetic or mechanical stirrer. This review takes stock of alternative technologies currently available in laboratories that facilitate the synthesis of such complexes. We highlight five such technologies: mechanochemistry, also known as solvent-free chemistry, uses a mortar and pestle or a ball mill; microwave activation can drastically reduce reaction times; ultrasonic activation promotes chemical reactions because of cavitation phenomena; photochemistry, which uses light radiation to initiate reactions; and continuous flow chemistry, which is increasingly used to simplify scale-up. While facilitating the synthesis of organometallic compounds, these enabling technologies also allow access to compounds that cannot be obtained in any other way. This shows how the paradigm is changing and evolving toward new technologies, without necessarily abandoning the round-bottom flask. A bright future is ahead of the organometallic chemist, thanks to these novel technologies.
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Affiliation(s)
- Audrey Beillard
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, Campus Triolet, Place Eugène Bataillon, 34095 Montpellier cedex 5, France
| | - Xavier Bantreil
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, Campus Triolet, Place Eugène Bataillon, 34095 Montpellier cedex 5, France
| | - Thomas-Xavier Métro
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, Campus Triolet, Place Eugène Bataillon, 34095 Montpellier cedex 5, France
| | - Jean Martinez
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, Campus Triolet, Place Eugène Bataillon, 34095 Montpellier cedex 5, France
| | - Frédéric Lamaty
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, Campus Triolet, Place Eugène Bataillon, 34095 Montpellier cedex 5, France
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Datta P, Sardar D, Panda U, Halder A, Manik NB, Chen CJ, Sinha C. Coumarinyl azoimidazolyl complexes of osmium(II) hydridocarbonyls: spectroscopic and structural characterization, oxidation catalysis, photovoltaic effect and density functional theory computation. Appl Organomet Chem 2016. [DOI: 10.1002/aoc.3435] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Papia Datta
- Department of Chemistry, Inorganic Chemistry Section; Jadavpur University; Kolkata 700032 India
- Department of Basic Science and Humanities; RCC Institute of Information Technology; Canal South Road, Beliaghata Kolkata 700015 India
| | - Dibakar Sardar
- Department of Chemistry, Inorganic Chemistry Section; Jadavpur University; Kolkata 700032 India
- Department of Chemistry; Dinabandhu Andrews College; Garia Kolkata 700084 India
| | - Uttam Panda
- Department of Chemistry, Inorganic Chemistry Section; Jadavpur University; Kolkata 700032 India
| | - Ajanta Halder
- Department of Physics; Jadavpur University; Kolkata 700032 India
| | | | - Chun-Jung Chen
- Life Science Group; National Synchrotron Radiation Research Centre; 101 Hsin Ann Road Hsinchu 30076 Taiwan
| | - Chittaranjan Sinha
- Department of Chemistry, Inorganic Chemistry Section; Jadavpur University; Kolkata 700032 India
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Dabb SL, Fletcher NC. mer and fac isomerism in tris chelate diimine metal complexes. Dalton Trans 2015; 44:4406-22. [PMID: 25600485 DOI: 10.1039/c4dt03535f] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this perspective, we highlight the issue of meridional (mer) and facial (fac) orientation of asymmetrical diimines in tris-chelate transition metal complexes. Diimine ligands have long been the workhorse of coordination chemistry, and whilst there are now good strategies to isolate materials where the inherent metal centered chirality is under almost complete control, and systematic methodologies to isolate heteroleptic complexes, the conceptually simple geometrical isomerism has not been widely investigated. In systems where the two donor atoms are significantly different in terms of the σ-donor and π-accepting ability, the fac isomer is likely to be the thermodynamic product. For the diimine complexes with two trigonal planar nitrogen atoms there is much more subtlety to the system, and external factors such as the solvent, lattice packing and the various steric considerations play a delicate role in determining the observed and isolable product. In this article we discuss the possibilities to control the isomeric ratio in labile systems, consider the opportunities to separate inert complexes and discuss the observed differences in their spectroscopic properties. Finally we report on the ligand orientation in supramolecular systems where facial coordination leads to simple regular structures such as helicates and tetrahedra, but the ability of the ligand system to adopt a mer orientation enables self-assembled structures of considerable beauty and complexity.
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Affiliation(s)
- Serin L Dabb
- School of Chemistry and Chemical Engineering, Queen's University of Belfast, David Keir Building, Belfast, Northern Ireland BT9 5AG, UK.
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Syntheses, structures, spectroscopic, electrochemical properties and DFT calculation of Ru(II)–thioarylazoimidazole complexes. J Organomet Chem 2009. [DOI: 10.1016/j.jorganchem.2009.06.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Osmium-carbonyl complexes of naphthylazoimidazoles. Single crystal X-ray structure of [Os(H)(CO)(PPh3)2(α-NaiEt)](PF6) {α-NaiEt=1-ethyl-2-(naphthyl-α-azo)imidazole}. Polyhedron 2007. [DOI: 10.1016/j.poly.2006.08.028] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Banerjee D, Ray U, Jasimuddin S, Liou JC, Lu TH, Sinha C. Copper(II) complexes of thioether containing an azoimidazolyl system. X-ray structure of Cu(SEtaaiNEt)Cl2 (SEtaaiNEt=1-ethyl-2-{(o-thioethyl)phenylazo}imidazole). Polyhedron 2006. [DOI: 10.1016/j.poly.2005.08.053] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ruthenium-mediated Selective Aromatic Thiolation in the Complex [RuII{o-S—C6H4-(p-R-)—N=N—C3H2NN(1)—R′}2]. Synthesis, Spectroscopic, e.p.r., Electro-chemical Characterization and Spectro-electrochemical Correlation. TRANSIT METAL CHEM 2005. [DOI: 10.1007/s11243-005-6288-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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A novel series of sulphur-bridged ruthenium-molybdenum complexes: [(RaaiR′)2 Ru(μ-S)2Mo(OH)2]. Synthesis, spectroscopic and electrochemical characterization. RaaiR′=1-alkyl-2-(arylazo) imidazole. TRANSIT METAL CHEM 2005. [DOI: 10.1007/s11243-005-4051-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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