Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Spin–Spin Coupling: One-Bond Coupling01:17

Spin–Spin Coupling: One-Bond Coupling

1.6K
Coupling interactions are strongest between NMR-active nuclei bonded to each other, where spin information can be transmitted directly through the pair of bonding electrons. While nuclei polarize their electrons to the opposite spins, the bonding electron pair has opposite spins. Configurations with antiparallel nuclear spins are expected to be lower in energy. When coupling makes antiparallel states more favorable, J is considered to have a positive value. The one-bond coupling constant, 1J,...
1.6K
Spin–Spin Coupling Constant: Overview01:08

Spin–Spin Coupling Constant: Overview

1.6K
In bromoethane, the three methyl protons are coupled to the two methylene protons that are three bonds away. In accordance with the n+1 rule, the signal from the methyl protons is split into three peaks with 1:2:1 relative intensities. The methylene protons appear as a quartet, with the relative intensities of 1:3:3:1.
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
1.6K
Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)01:22

Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)

1.6K
Vicinal or three-bond coupling is commonly observed between protons attached to adjacent carbons. Here, nuclear spin information is primarily transferred via electron spin interactions between adjacent C‑H bond orbitals. This generally favors the antiparallel arrangement of spins, so 3J values are usually positive.
The extent of coupling depends on the C‑C bond length, the two H‑C‑C angles, any electron-withdrawing substituents, and the dihedral angle between the involved orbitals. The...
1.6K
¹H NMR: Long-Range Coupling01:27

¹H NMR: Long-Range Coupling

2.8K
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...
2.8K
Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)01:20

Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)

1.9K
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
1.9K
Metal-Ligand Bonds02:51

Metal-Ligand Bonds

25.3K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
25.3K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Age-Dependent z Scores and eGFR-Adjusted Reference Ranges for Neurofilament Light: A Practical Approach for Clinical Laboratories.

Clinical chemistry·2026
Same author

Indirect optical geometry measurement based on optical tweezers in transparent microchannels.

Optics express·2026
Same author

Correction: Intraperitoneal Oil Application Causes Local Inflammation with Depletion of Resident Peritoneal Macrophages.

Molecular cancer research : MCR·2026
Same author

Identification of serum biomarkers linking myocardial fibrosis, systolic dysfunction and outcomes in patients with severe aortic stenosis.

Cardiovascular research·2026
Same author

Three reversibly interconvertible redox states of boradigermaallyl: syntheses of radical allyl anion and allyl dianion.

Chemical science·2026
Same author

Molecular characterization of cell decay in inflammation and topological assignment of released cfDNA for integrative laboratory and radiological outcome assessment.

Frontiers in cellular and infection microbiology·2026

Related Experiment Video

Updated: Mar 16, 2026

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
09:37

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry

Published on: October 18, 2019

10.2K

J(Si,H) Coupling Constants in Nonclassical Transition-Metal Silane Complexes.

Wolfgang Scherer1, Petra Meixner2, Kilian Batke2

  • 1Institut für Physik, Universität Augsburg, Universitätsstrasse 1, 86135, Augsburg, Germany. wolfgang.scherer@physik.uni-augsburg.de.

Angewandte Chemie (International Ed. in English)
|August 10, 2016
PubMed
Summary
This summary is machine-generated.

The sign and magnitude of silicon-hydrogen (Si-H) coupling constants precisely measure Si-H bond activation in silane complexes. Correcting literature errors reveals key control parameters for this activation process.

Keywords:
MO analysisNMR spectroscopycharge densitycoupling constantsnonclassical silane complexes

More Related Videos

Attaching Biological Probes to Silica Optical Biosensors Using Silane Coupling Agents
09:35

Attaching Biological Probes to Silica Optical Biosensors Using Silane Coupling Agents

Published on: May 1, 2012

13.5K
Generation of Zerovalent Metal Core Nanoparticles Using n-2-aminoethyl-3-aminosilanetriol
08:12

Generation of Zerovalent Metal Core Nanoparticles Using n-2-aminoethyl-3-aminosilanetriol

Published on: February 11, 2016

8.2K

Related Experiment Videos

Last Updated: Mar 16, 2026

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
09:37

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry

Published on: October 18, 2019

10.2K
Attaching Biological Probes to Silica Optical Biosensors Using Silane Coupling Agents
09:35

Attaching Biological Probes to Silica Optical Biosensors Using Silane Coupling Agents

Published on: May 1, 2012

13.5K
Generation of Zerovalent Metal Core Nanoparticles Using n-2-aminoethyl-3-aminosilanetriol
08:12

Generation of Zerovalent Metal Core Nanoparticles Using n-2-aminoethyl-3-aminosilanetriol

Published on: February 11, 2016

8.2K

Area of Science:

  • Organometallic Chemistry
  • Inorganic Chemistry
  • Spectroscopy

Background:

  • Nonclassical silane complexes are crucial in catalysis.
  • Understanding silicon-hydrogen (Si-H) bond activation is key to controlling reactivity.
  • Previous literature contained errors in determining J(Si,H) coupling constant signs.

Purpose of the Study:

  • To establish J(Si,H) coupling constants as a sensitive measure of Si-H bond activation.
  • To correct erroneous J(Si,H) sign determinations in the literature.
  • To identify critical parameters controlling Si-H bond activation in silane complexes.

Main Methods:

  • Nuclear Magnetic Resonance (NMR) spectroscopy was used to measure J(Si,H) coupling constants.
  • Computational chemistry methods were employed to analyze electronic structures and bonding.
  • Synthesis and characterization of novel nonclassical silane complexes were performed.

Main Results:

  • The sign and magnitude of J(Si,H) coupling constants directly correlate with the extent of Si-H bond activation.
  • Accurate J(Si,H) sign determinations were established, resolving literature discrepancies.
  • Key electronic and steric factors influencing Si-H bond activation were identified.

Conclusions:

  • J(Si,H) coupling constants are a reliable and sensitive probe for Si-H bond activation in nonclassical silane complexes.
  • Corrected understanding of J(Si,H) facilitates precise control over silane complex reactivity.
  • This work provides a foundation for designing improved catalysts based on silane activation principles.