Video Experimental Relacionado

Updated: Jul 10, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
10:44

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals

Published on: April 19, 2019

Acoplamiento de intercambio mediado a través de enlaces y a través del espacio en andamios poliradicales

Andrzej Rajca1, Sumit Mukherjee, Maren Pink

  • 1Department of Chemistry, University of Nebraska, Lincoln, NE 68588-0304, USA. arajca1@unl.edu

Journal of the American Chemical Society
|October 13, 2006
PubMed
Resumen

Los poliradicales de calix[4]areno sintetizados revelan la dependencia conformacional del acoplamiento de intercambio magnético. El acoplamiento a través del enlace es ferromagnético en el cono y antiferromagnético en las conformaciones 1,3-alternativas, mientras que el acoplamiento a través del espacio es antiferromagnético en ambos.

Más Videos Relacionados

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy07:36

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy

Published on: November 9, 2019

Synthesis of Triazole and Tetrazole-Functionalized Zr-Based Metal-Organic Frameworks Through Post-Synthetic Ligand Exchange04:51

Synthesis of Triazole and Tetrazole-Functionalized Zr-Based Metal-Organic Frameworks Through Post-Synthetic Ligand Exchange

Published on: June 23, 2023

Videos de Conceptos Relacionados

Hybridization of Atomic Orbitals II03:35

Hybridization of Atomic Orbitals II

sp3d and sp3d 2 Hybridization
Coordination Number and Geometry02:57

Coordination Number and Geometry

For transition metal complexes, the coordination number determines the geometry around the central metal ion. Table 1 compares coordination numbers to molecular geometry. The most common structures of the complexes in coordination compounds are octahedral, tetrahedral, and square planar.
Structural Isomerism02:34

Structural Isomerism

Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
Isomerism in Alkenes02:01

Isomerism in Alkenes

Alkenes like 1-butene and 2-butene exhibit constitutional isomerism, as they differ in the position of the double bond. Further, 2-butene exhibits stereoisomerism and exists as two distinct compounds differing in spatial arrangement.
An isomer is called cis-2-butene when the methyl groups are on the same side of the double bond, and the other stereoisomer, in which methyl groups are on the opposite side of the double bond, is called trans-2-butene. The cis and trans stereoisomers are not...
[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement01:21

[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement

The Cope rearrangement is classified as a [3,3] sigmatropic shift in 1,5-dienes, leading to a more stable, isomeric 1,5-diene. The reaction involves a concerted movement of six electrons, four from two π bonds and two from a σ bond, via an energetically favorable chair-like transition state.
¹H NMR: Long-Range Coupling01:27

¹H NMR: Long-Range Coupling

The coupling interactions of nuclei across four or more bonds are usually weak, with J values less than 1 Hz. While these are usually not observed in spectra, the presence of multiple bonds along the coupling pathway can result in observable long-range coupling.
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene π orbitals.