Video Experimental Relacionado

Updated: Jul 6, 2026

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphos^Ph Complexes

Published on: April 10, 2015

El anillo de piridina se abre a temperatura ambiente en un complejo de bipiridina tricarbonilo de renio

Miguel A Huertos¹, Julio Pérez, Lucía Riera

¹Departamento de Química Orgánica e Inorgánica-IUQOEM, Facultad de Química, Universidad de Oviedo-CSIC, 33006 Oviedo, Spain.

Journal of the American Chemical Society

|April 10, 2008

Resumen

Este estudio detalla la apertura del anillo de piridina en complejos de renio. Los investigadores lograron esto reaccionando un complejo de metilimidazol-bipiridina-renio con un agente sililador, seguido de una metilación.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
Coordinación Química de la Coordinación
Química sintética de la química sintética.

Sus antecedentes:

Los complejos de renio con los ligandos de imidazol y bipiridina son de interés por su reactividad única.
Comprender la reactividad de los ligandos que contienen piridina en complejos organometálicos es crucial para el desarrollo de nuevas metodologías sintéticas.

Objetivo del estudio:

Para investigar las reacciones de apertura de anillos de los ligandos que contienen piridina en los complejos de renio.
Para explorar los efectos de diferentes análogos de imidazol y bipiridina en el resultado de la reacción.

Principales métodos:

Síntesis de complejos de renio con metilimidazol (MeIm) y 2,2'-bipiridina (bipy) ligandos.
Reacción del complejo de renio con la amida de bis ((trimetilsililo) potasio (KN ((SiMe3) 2) para inducir la desprotonación.
Posteriormente, se realizó una doble metilación con trifluorometano sulfonato de metilo.
Aislamiento y caracterización de productos intermedios y productos utilizando ligandos modificados como el mesitylimidazol (MesIm) y la 1,10-fenantrolina (phen).

Principales resultados:

Observación de la apertura del anillo de piridina en el complejo de renio bajo condiciones de reacción específicas.
Se han aislado con éxito análogos del producto de desprotonación y del primer producto de metilación.
Se ha demostrado que el uso de mesitylimidazole (MesIm) o 1,10-phenanthroline (phen) ligandos permite el aislamiento de los intermediarios y productos relacionados.

Conclusiones:

La apertura del anillo de piridina es una vía de reacción viable para [Re (((CO) 3 (((MeIm) (((bipy) ]OTf en condiciones de desprotonación y metilación.
El uso de ligandos estéricamente impedidos o modificados electrónicamente (MesIm, fen) facilita el aislamiento de los intermediarios clave, lo que ayuda a la comprensión mecánica.

Más Videos Relacionados

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex

Published on: July 27, 2022

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization

Published on: November 29, 2018

Videos de Conceptos Relacionados

Thermal Electrocyclic Reactions: Stereochemistry

Thermal Electrocyclic Reactions: Stereochemistry

The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.

Thermal and Photochemical Electrocyclic Reactions: Overview

Thermal and Photochemical Electrocyclic Reactions: Overview

Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.

Base-Catalyzed Ring-Opening of Epoxides

Base-Catalyzed Ring-Opening of Epoxides

Due to their highly strained structures, epoxides can readily undergo ring-opening reactions through nucleophilic substitution, either in the presence of an acid or a base. The nucleophilic substitution reactions in the presence of acid are called acid-catalyzed ring-opening reactions, and nucleophilic substitution reactions in the presence of a base are called base-catalyzed ring-opening reactions. Epoxides undergo base-catalyzed ring-opening reactions in the presence of a strong nucleophile...

Olefin Metathesis Polymerization: Ring-Opening Metathesis Polymerization (ROMP)

Olefin Metathesis Polymerization: Ring-Opening Metathesis Polymerization (ROMP)

Ring-opening metathesis polymerization or ROMP involves strained cycloalkenes as starting materials. The mechanism of ROMP proceeds by reacting cycloalkene with Grubbs catalyst to give metallacyclobutane intermediate which undergoes a ring-opening reaction to form new carbene. The new carbene reacts with another molecule of cycloalkene. Repetition of these steps leads to the formation of an unsaturated open-chain polymer product. All these steps are reversible, however, relieving the ring...

Aromatic Hydrocarbon Cations: Structural Overview

Aromatic Hydrocarbon Cations: Structural Overview

Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group with both...

Acid-Catalyzed Ring-Opening of Epoxides

Acid-Catalyzed Ring-Opening of Epoxides

Epoxides that are three-membered ring systems are more reactive than other cyclic and acyclic ethers. The high reactivity of epoxides originates from the strain present in the ring. This ring strain acts as a driving force for epoxides to undergo ring-opening reactions either with halogen acids or weak nucleophiles in the presence of mild acid. The acid catalyst converts the epoxide oxygen, a poor leaving group, into an oxonium ion, a better leaving group, making the reaction feasible. The...