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Cañadas P, Díaz J, López R, Menéndez MI, Pérez J, Riera L. Elucidation of the Pyridine Ring-Opening Mechanism of 2,2'-Bipyridine or 1,10-Phenanthroline Ligands at Re(I) Carbonyl Complexes. Inorg Chem 2024; 63:8593-8603. [PMID: 38640477 DOI: 10.1021/acs.inorgchem.3c04434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/21/2024]
Abstract
The cleavage of the C-N bonds of aromatic heterocycles, such as pyridines or quinolines, is a crucial step in the hydrodenitrogenation (HDN) industrial processes of fuels in order to minimize the emission of nitrogen oxides into the atmosphere. Due to the harsh conditions under which these reactions take place (high temperature and H2 pressure), the mechanism by which they occur is only partially understood, and any study at the molecular level that reveals new mechanistic possibilities in this area is of great interest. Herein, we unravel the pyridine ring-opening mechanism of 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen) ligands coordinated to the cis-{Re(CO)2(N-RIm)(PMe3)} (N-RIm= N-alkylimidazole) fragment under mild conditions. Computational calculations show that deprotonation of the pyridine ring, once dearomatized, is crucial to induce ring contraction, triggering extrusion of the nitrogen atom from the ring and cleavage of the C-N bond. It is noteworthy that different products (regioisomers) are obtained depending on whether the ligand used is bipy or phen due to the additional rigidity and stability conferred by the central ring of the phen ligand, an issue also addressed and clarified computationally. Strong support for the proposed mechanism is provided by the characterization and isolation, including three single-crystal X-ray diffraction structures, of several of the proposed reaction intermediates.
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Affiliation(s)
- Purificación Cañadas
- Departamento de Química Orgánica e Inorgánica, Universidad de Oviedo, Julián Clavería, 8, Oviedo 33006, Spain
| | - Jesús Díaz
- Departamento de Química Orgánica e Inorgánica, Universidad de Extremadura, Avda. de la Universidad s/n, Cáceres 33071, Spain
| | - Ramón López
- Departamento de Química Física y Analítica, Universidad de Oviedo, Julián Clavería, 8, Oviedo 33006, Spain
| | - M Isabel Menéndez
- Departamento de Química Física y Analítica, Universidad de Oviedo, Julián Clavería, 8, Oviedo 33006, Spain
| | - Julio Pérez
- Departamento de Química Orgánica e Inorgánica, Universidad de Oviedo, Julián Clavería, 8, Oviedo 33006, Spain
- Centro de Investigación en Nanomateriales y Nanotecnología (CINN), Consejo Superior de Investigaciones Científicas (CSIC). Avda. de la Vega, 4-6, El Entrego 33940, Spain
| | - Lucía Riera
- Centro de Investigación en Nanomateriales y Nanotecnología (CINN), Consejo Superior de Investigaciones Científicas (CSIC). Avda. de la Vega, 4-6, El Entrego 33940, Spain
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Cañadas P, Díaz J, Pérez J, Riera L. Strongly Electron-Donating Triazolylidene Ligands: Cationic Metal Carbonyl Complexes of 1-Methyl-1,2,3-triazole as Triazolium Surrogates. Inorg Chem 2022; 61:1254-1258. [PMID: 34990546 DOI: 10.1021/acs.inorgchem.1c03254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new strategy for tuning the electronic properties of 1,2,3-triazol-5-ylidene metal complexes is reported using {Mo(η3-C4H7)(bipy)(CO)2} or {Re(bipy)(CO)3} fragments as substituents at the triazole N3 atom. The reaction of cationic molybdenum(II) and rhenium(I) 1-methyl-1,2,3-triazole compounds with the strong base KN(SiMe3)2 in the presence of electrophilic metal fragments, such as AgOTf (OTf = trifluoromethanesufonate) or [CuCl(IPr)] [IPr = 2,6-(diisopropyl)phenylimidazol-2-ylidene] affords a new type of 1,2,3-triazol-5-ylidene complexes. For silver(I) cationic bis(triazolylidene), [Ag(tzNHCM)2]OTf (M = [Mo], 2; [Re], 4), complexes are obtained, whereas in the case of Cu(I) mixed normal/mesoionic NHC, [Cu(IPr)(tzNHCM)]OTf (M = [Mo], 7; [Re], 8) complexes are formed. This special type of mesoionic N-heterocyclic carbenes bear a metal fragment at the N3 atom of the 1,2,3-triazole moiety, showing notable enhancement of the carbene electron donor ability compared to conventional alkyl-substituted analogues. Transmetalation from cationic silver bis(triazolylidene) complexes 2 and 4, prepared using this methodology, has proven to be very efficient toward [M'Cl(cod)]2 (M' = Rh, Ir; cod = 1,5-cyclooctadiene), affording the corresponding cationic bis(triazolylidene) [M'(cod)(tzNHCM)2]OTf (9-12) complexes. A subsequent reaction with CO(g) easily produces substitution of the diene ligand, affording the corresponding cis-dicarbonyl [M'(CO)2(tzNHCM)2]OTf (13-16) compounds.
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Affiliation(s)
- Purificación Cañadas
- Departamento de Química Orgánica e Inorgánica, Universidad de Oviedo, Julián Clavería 8, 33006 Oviedo, Spain
| | - Jesús Díaz
- Departamento de Química Orgánica e Inorgánica, Universidad de Extremadura, Avenida de la Universidad s/n, 33071 Cáceres, Spain
| | - Julio Pérez
- Departamento de Química Orgánica e Inorgánica, Universidad de Oviedo, Julián Clavería 8, 33006 Oviedo, Spain.,Centro de Investigación en Nanomateriales y Nanotecnología, Consejo Superior de Investigaciones Científicas, Avenida de la Vega 4-6, 33940 El Entrego, Spain
| | - Lucía Riera
- Centro de Investigación en Nanomateriales y Nanotecnología, Consejo Superior de Investigaciones Científicas, Avenida de la Vega 4-6, 33940 El Entrego, Spain
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3
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Arevalo R, López R, Falvello LR, Riera L, Perez J. Building C(sp 3 ) Molecular Complexity on 2,2'-Bipyridine and 1,10-Phenanthroline in Rhenium Tricarbonyl Complexes. Chemistry 2021; 27:379-389. [PMID: 33001533 DOI: 10.1002/chem.202003814] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 09/12/2020] [Indexed: 12/21/2022]
Abstract
The reactions of [Re(N-N)(CO)3 (PMe3 )]OTf (N-N=2,2'-bipyridine, bipy; 1,10-phenanthroline, phen) compounds with tBuLi and with LiHBEt3 have been explored. Addition to the N-N chelate took place with different site-selectivity depending on both chelate and nucleophile. Thus, with tBuLi, an unprecedented addition to C5 of bipy, a regiochemistry not accessible for free bipy, was obtained, whereas coordinated phen underwent tBuLi addition to C2 and C4. Remarkably, when LiHBEt3 reacted with [Re(bipy)(CO)3 (PMe3 )]OTf, hydride addition to the 4 and 6 positions of bipy triggered an intermolecular cyclodimerization of two dearomatized pyridyl rings. In contrast, hydride addition to the phen analog resulted in partial reduction of one pyridine ring. The resulting neutral ReI products showed a varied reactivity with HOTf and with MeOTf to yield cationic complexes. These strategies rendered access to ReI complexes containing bipy- and phen-derived chelates with several C(sp3 ) centers.
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Affiliation(s)
- Rebeca Arevalo
- Departamento de Química Orgánica e Inorgánica, Universidad de Oviedo, Julián Clavería, 8, 33006, Oviedo, Spain.,Current address: Department of Chemistry and Chemical Biology, University of California, Merced, 5200 N. Lake Road, 95343, Merced, CA, USA
| | - Ramón López
- Departamento de Química Física y Analítica, Universidad de Oviedo, Julián Clavería, 8, 33006, Oviedo, Spain
| | - Larry R Falvello
- Departamento de Química Inorgánica, Instituto de Ciencia de Materiales de Aragón (ICMA), Universidad de Zaragoza-CSIC, 50009, Zaragoza, Spain
| | - Lucía Riera
- Departamento de Química Orgánica e Inorgánica, Universidad de Oviedo, Julián Clavería, 8, 33006, Oviedo, Spain.,Centro de Investigación en Nanomateriales y Nanotecnología-CINN, CSIC- Universidad de Oviedo-Principado de Asturias, Avda. de la Vega 4-6, 33940, El Entrego, Spain
| | - Julio Perez
- Departamento de Química Orgánica e Inorgánica, Universidad de Oviedo, Julián Clavería, 8, 33006, Oviedo, Spain.,Centro de Investigación en Nanomateriales y Nanotecnología-CINN, CSIC- Universidad de Oviedo-Principado de Asturias, Avda. de la Vega 4-6, 33940, El Entrego, Spain
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Espinal‐Viguri M, Fombona S, Álvarez D, Díaz J, Menéndez MI, López R, Pérez J, Riera L. Regiochemistry Control by Bipyridine Substituents in the Deprotonation of Re
I
and Mo
II
N
‐Alkylimidazole Complexes. Chemistry 2019; 25:9253-9265. [DOI: 10.1002/chem.201901060] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 04/25/2019] [Indexed: 12/12/2022]
Affiliation(s)
- Maialen Espinal‐Viguri
- Departamento de Química Orgánica e InorgánicaUniversidad de Oviedo C/ Julián Clavería, 8. 33006 Oviedo Spain
| | - Sergio Fombona
- Departamento de Química Orgánica e InorgánicaUniversidad de Oviedo C/ Julián Clavería, 8. 33006 Oviedo Spain
| | - Daniel Álvarez
- Departamento de Química Física y AnalíticaUniversidad de Oviedo C/ Julián Clavería, 8. 33006 Oviedo Spain
| | - Jesús Díaz
- Departamento de Química Orgánica e InorgánicaUniversidad de Extremadura Avda. de la Universidad s/n. 10071 Cáceres Spain
| | - M. Isabel Menéndez
- Departamento de Química Física y AnalíticaUniversidad de Oviedo C/ Julián Clavería, 8. 33006 Oviedo Spain
| | - Ramón López
- Departamento de Química Física y AnalíticaUniversidad de Oviedo C/ Julián Clavería, 8. 33006 Oviedo Spain
| | - Julio Pérez
- Centro de Investigación en Nanomateriales y Nanotecnología-CINNCSIC-Universidad de Oviedo-Principado de Asturias Avda. de la Vega 4–6 33940 El Entrego Spain
- Departamento de Química Orgánica e InorgánicaUniversidad de Oviedo C/ Julián Clavería, 8. 33006 Oviedo Spain
| | - Lucía Riera
- Centro de Investigación en Nanomateriales y Nanotecnología-CINNCSIC-Universidad de Oviedo-Principado de Asturias Avda. de la Vega 4–6 33940 El Entrego Spain
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Aminzadeh M, Eslami A, Kia R, Aleeshah R. Synthesis, crystal structure and DNA interaction of a new water-soluble derivative of pyrazino[2,3-f][1,10] phenanthroline; theoretical calculations, experimental and molecular docking studies. J Mol Struct 2018. [DOI: 10.1016/j.molstruc.2018.03.117] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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