Video Experimental Relacionado

Updated: Jan 8, 2026

Protocol for the Solid-phase Synthesis of Oligomers of RNA Containing a 2'-O-thiophenylmethyl Modification and Characterization via Circular Dichroism

Protocol for the Solid-phase Synthesis of Oligomers of RNA Containing a 2'-O-thiophenylmethyl Modification and Characterization via Circular Dichroism

Published on: July 28, 2017

Delineación de las vías de deambulación y no deambulación para la liberación de NO en o-nitrofurano y o-nitrotioteno

Sumitra Singh¹, Supriyo Santra², Shaivi Kesari¹

¹Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, India. naresh@chem.iitb.ac.in.

Chemical communications (Cambridge, England)

|December 23, 2025

Abstract:

The delineation of NO₂ roaming and oxaziridine pathways for NO release is experimentally demonstrated using o-nitrofuran and o-nitrothiophene in lieu of nitrobenzene. The excitation energy dependence of the NO translational energy allows demarcation of the NO₂ roaming and oxaziridine pathways above and below 4.66 eV, respectively. Quantum chemical calculations indicate that the roaming pathway can be accessed following T₁/S₀ crossing at 4.89 eV, which is energetically above the oxaziridine pathway at 4.50 eV.

Palabras clave:

fotólisis óxido nítrico nitroaromáticos química cuántica cinética química

Más Videos Relacionados

Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development

Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development

Published on: April 15, 2013

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives

Published on: January 19, 2016

Videos de Conceptos Relacionados

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...

ortho–para-Directing Activators: –CH3, –OH, –&NoBreak;NH2, –OCH3

ortho–para-Directing Activators: –CH₃, –OH, –⁠NH₂, –OCH₃

All ortho–para directors, excluding halogens, are activating groups. These groups donate electrons to the ring, making the ring carbons electron-rich. Consequently, the reactivity of the aromatic ring towards electrophilic substitution increases. For instance, the nitration of anisole is about 10,000 times faster than the nitration of benzene. The electron-donating effect of the methoxy group in anisole activates the ortho and para positions on the ring and stabilizes the corresponding...

Nuclear Overhauser Enhancement (NOE)

Nuclear Overhauser Enhancement (NOE)

Irradiation of a spin-active nucleus causes an increase or decrease in the signal intensity of neighboring nuclei that are not necessarily chemically bonded or involved in J-coupling. This phenomenon, called the nuclear Overhauser enhancement (NOE), results from through-space interactions between the nuclear spins. The NOE effect decreases with increasing internuclear distance and is generally not observed beyond 4 angstroms. In NOE, dipole-dipole interactions between neighboring spin-active...