Video Experimental Relacionado

Updated: Aug 4, 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

Adición de un radical de nitróxido estable a los compuestos divalentes estables de los elementos más pesados del

Takeaki Iwamoto¹, Hidenori Masuda, Shintaro Ishida

¹Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.

Journal of the American Chemical Society

|August 2, 2003

Resumen

El germileno cíclico estable y el dialquilstanileno reaccionan con los radicales TEMPO para formar aductos. El germileno es el germileno.

Área de la Ciencia:

Química organometálica de las sustancias orgánicas.
Química de los radicales libres en la química de los radicales libres.

Sus antecedentes:

Los germilenos, estanilenos y sililenos cíclicos estables son intermediarios reactivos.
Los radicales de nitróxido como TEMPO son ampliamente utilizados en diversas aplicaciones químicas.

Objetivo del estudio:

Para investigar las vías de reacción del dialquilgermileno, dialquilstanileno y dialquilsilileno con los radicales TEMPO.
Para dilucidar la cinética y el mecanismo de la adición de TEMPO al germileno.
Para explorar la reactividad contrastante del silileno con TEMPO.

Principales métodos:

La espectroscopia de resonancia magnética nuclear (RMN) también se conoce como espectroscopia de resonancia magnética nuclear.
La espectrometría de masas (MS)
Cristalografía de rayos X con rayos X.
Estudios cinéticos y estudios de movimiento.

Principales resultados:

Se sintetizaron y caracterizaron adutos 1:2 de germileno (2) y estanileno (3) con TEMPO (2,2,6,6-tetrametilpiperidinil-1-oxy).
El análisis cinético reveló una adición inicial de TEMPO 1010 veces más lenta al germileno en comparación con la segunda adición al radical germilo.
Dialquilisileno (1) reaccionó con TEMPO para producir un derivado único de 1,3-dioxadisileno, diferente de las reacciones de germileno y estanileno.

Conclusiones:

La diferencia cinética observada en la adición de TEMPO al germileno se explica por la teoría de la perturbación cualitativa.
El resultado de reacción distinto para el silene sugiere propiedades electrónicas únicas que influyen en su reactividad con los radicales.

Más Videos Relacionados

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes

Published on: July 28, 2018

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones

Published on: January 21, 2020

Videos de Conceptos Relacionados

Noble Gases

Noble Gases

The elements in group 18 are noble gases (helium, neon, argon, krypton, xenon, and radon). They earned the name “noble” because they were assumed to be nonreactive since they have filled valence shells. In 1962, Dr. Neil Bartlett at the University of British Columbia proved this assumption to be false.

meta-Directing Deactivators: –NO2, –CN, –CHO, –&NoBreak;CO2R, –COR, –CO2H

meta-Directing Deactivators: –NO₂, –CN, –CHO, –⁠CO₂R, –COR, –CO₂H

All meta-directing substituents are deactivating groups. These substituents withdraw electrons from the aromatic ring, making the ring less reactive toward electrophilic substitution. For example, the nitration of nitrobenzene is 100,000 times slower than that of benzene because of the deactivating effect of the nitro group. The first step in an electrophilic aromatic substitution is the addition of an electrophile to form a resonance-stabilized carbocation. The energy diagrams for the...

1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview

1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO₂ Overview

Nitrous acid and nitric acids are two types of acids containing nitrogen, among which nitrous acid is weaker than nitric acid. Nitrous acid with a pKa value of 3.37 ionizes in water to give a nitrite ion and the hydronium ion.
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by water loss...

Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions

Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions

Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. For instance, arenediazonium salts react with copper(I) salts of chloride, bromide, or cyanide to form corresponding aryl chlorides, bromides, and nitriles. These reactions are named Sandmeyer reactions. Although the mechanism of this reaction is complicated, as illustrated in Figure 1, they are believed to progress via an aryl copper...

Diazonium Group Substitution: –OH and –H

Diazonium Group Substitution: –OH and –H

Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.

Radical Formation: Addition

Radical Formation: Addition

Radicals can be formed by adding a radical to a spin-paired molecule. This is typically observed with unsaturated species, where the addition of a radical across the π bond leads to the production of a new radical by dissolving the π bond. For example, the addition of a Br radical to an alkene yields a carbon-centered radical.
Similar to charge conservation in chemical reactions, spin conservation is implicit for radical reactions. Accordingly, the product formed must possess an unpaired...