Resonance Stabilized Anion
Resonance Stabilized Anion - Related Videos
10:53
Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by π-π Stacking Interactions
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Cited by 2 •
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The key steps of living anionic polymerization of phenyl glycidyl ether (PheGE) on methoxy-polyethylene glycol (mPEG-b-PPheGE) are described. The resulting block copolymer micelles (BCMs) were loaded with doxorubicin 14% (wt%) and sustained release of drug over 4 days under physiologically relevant conditions was obtained.
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Detection of Nitric Oxide and Superoxide Radical Anion by Electron Paramagnetic Resonance Spectroscopy from Cells using Spin Traps
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2012
Electron paramagnetic resonance (EPR) spectroscopy was employed to detect nitric oxide from bovine aortic endothelial cells and superoxide radical anion from human neutrophils using iron (II)-N-methyl-D-glucamine dithiocarbamate, Fe(MGD)2 and 5,5-dimethyl-1-pyroroline-N-oxide, DMPO, respectively.
02:52
Resonance
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2020
The Lewis structure of a nitrite anion (NO2−) may actually be drawn in two different ways, distinguished by the locations of the N-O and N=O bonds. If nitrite ions do indeed contain a single and a double bond, the two bond lengths are expected to be different. A double bond between two atoms is shorter (and stronger) than a single bond between the same two atoms. However, experiments show that both N–O bonds in NO2− have the same strength and length, and are identical in all other...
02:38
Anion Exchange Resin–Based Detection of Viruses from Bioaerosols
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2026
Source: Schaeffer, J. W., Chandler, et al. Detection of Viruses from Bioaerosols Using Anion Exchange Resin. J. Vis. Exp. (2018).This video demonstrates the detection of viruses from bioaerosols using an anion exchange resin. A liquid impinger containing the resin is used to capture viruses from the air. The resin is collected and treated with a virus lysis buffer containing carrier RNA. The lysate is transferred to a microcentrifuge tube for viral RNA isolation, followed by qRT-PCR to amplify...
03:18
Nuclear Stability
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2020
Protons and neutrons, collectively called nucleons, are packed together tightly in a nucleus. With a radius of about 10−15 meters, a nucleus is quite small compared to the radius of the entire atom, which is about 10−10 meters. Nuclei are extremely dense compared to bulk matter, averaging 1.8 × 1014 grams per cubic centimeter. If the earth’s density were equal to the average nuclear density, the earth’s radius would be only about 200 meters. To hold positively charged protons together in the...
FAQs
Overlapping p orbitals provide a pathway for excess electron density to extend across adjacent atoms rather than remain concentrated at one site. This delocalization creates conjugated arrangements in which the negative charge is distributed among multiple atoms. Because the charge distribution lowers the anion’s energy, the resulting species is more stable than a comparable localized anion.
Oxygen can participate in charge delocalization within a conjugated anion, allowing the negative charge to be shared between carbon and an electronegative atom. This arrangement lowers the energy of the species more effectively than retaining the charge at a single carbon center. The effect is particularly important when analyzing enolates and related conjugate bases.
A conjugate acid becomes relatively more acidic when removal of its proton produces an especially stable anion. Resonance provides that stabilization by distributing the resulting negative charge across several atoms, and the effect becomes stronger when oxygen can share the charge. Comparing conjugate-base stability therefore helps predict relative acidity among compounds with acidic C–H bonds.
First consider the anion produced when the C–H bond loses a proton. Then determine whether adjacent atoms provide overlapping p orbitals that can distribute the negative charge through conjugation. If multiple valid Lewis structures place the charge at different connected atoms, the conjugate base has resonance stabilization, which helps explain its formation and relative stability.
These anion types illustrate how resonance stabilization connects structure with reactivity. Their delocalized negative charge allows them to persist as identifiable conjugate bases while still acting as nucleophiles. In organic chemistry, this behavior makes them important participants in carbon–carbon bond-forming reactions, where their nucleophilic character helps create new connections between carbon atoms.
The anion’s delocalization helps explain why it can serve as a nucleophile while distributing electron density across a conjugated system. Enolates, allylic anions, and benzylic anions are relevant examples. Examining their resonance forms identifies the stabilized reactive species and connects conjugate-base formation with the use of these anions in carbon–carbon bond-forming reactions.