Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

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...

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

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

Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.

Nitric Oxide Signaling Pathway

Nitric Oxide Signaling Pathway

Nitric oxide (NO), an inorganic gas, acts as a potent second messenger in most animal and plant tissues. NO diffuses out of the cells that produce it and enters the neighboring cells to generate a downstream response. NO synthase (NOS) catalyzes NO production by the deamination of the amino acid arginine. There are three isoforms of NOS. Endothelial cells have endothelial NOS (eNOS), nerve and muscle cells have neuronal NOS (nNOS), and macrophages produce inducible NOS (iNOS) upon exposure...

Resonance

Resonance

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.

Nitrosation of Enols

Nitrosation of Enols

The nitrosation reaction is one of the methods of preparing 1,2-diketones. The enol tautomer of the starting ketone reacts with sodium nitrite in hydrochloric acid, generating the 1,2-diketone after hydrolysis.

2° Amines to N-Nitrosamines: Reaction with NaNO2

2° Amines to N-Nitrosamines: Reaction with NaNO₂

Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.

You might also read

Related Articles

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

Sort by

Same author

Advanced treatment of biologically pretreated coal gasification wastewater by a novel integration of heterogeneous Fenton oxidation and biological process.

Bioresource technology·2015

Same author

Immunogenicity of the Bivalent Oral Cholera Vaccine Shanchol in Haitian Adults With HIV Infection.

The Journal of infectious diseases·2015

Same author

No Superiority of High-Flexion vs Standard Total Knee Arthroplasty: An Update Meta-Analysis of Randomized Controlled Trials.

The Journal of arthroplasty·2015

Same author

When plants produce not enough or at all: metabolic engineering of flavonoids in microbial hosts.

Frontiers in plant science·2015

Same author

Synthesis and molecular structure of the 5-methoxycarbonylpentyl α-glycoside of the upstream, terminal moiety of the O-specific polysaccharide of Vibrio cholerae O1, serotype Inaba.

Molecules (Basel, Switzerland)·2015

Same author

Comparative analysis of sequence feature and expression of two heat shock cognate 70 genes in mandarin fish Siniperca chuatsi.

Gene·2015

Same journal

Kinetic and Mechanistic Insights into H-Abstraction and Subsequent Isomerization and Decomposition of Monoglyme and Key Combustion Intermediates.

The journal of physical chemistry. A·2026

Same journal

First-Principles Analysis of Protonation-Induced Electronic Effects in Tetrakis(<i>p</i>-aminophenyl)porphyrin (TAPP).

The journal of physical chemistry. A·2026

Same journal

Exploring the Reactivity of the CH Radical toward Nitrous Oxide in the Context of the Interstellar Medium.

The journal of physical chemistry. A·2026

Same journal

Infrared Photodissociation Spectroscopy of Benzene-V<sup>+</sup>(CO)<sub>n</sub> "Piano Stool" Cations.

The journal of physical chemistry. A·2026

Same journal

Correction to "Solvent-Dependent Ultrafast Photochemical Dynamics of <i>N</i>-Methyl Oxindole Overcrowded Alkene Molecular Motors".

The journal of physical chemistry. A·2026

Same journal

Accelerating the Discovery of Superhalogens via Physics-Informed Graph Neural Networks.

The journal of physical chemistry. A·2026

See all related articles

Search research articles

Related Experiment Video

Updated: Mar 26, 2026

Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds

Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds

Published on: February 16, 2022

The Dimerization of H2NO.

Peng Xu¹, Roald Hoffmann¹

¹Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853-1301, United States.

The Journal of Physical Chemistry. A

|February 5, 2016

Summary

This summary is machine-generated.

The study explores the dimerization of H2NO, a persistent free radical. The most stable form is a strongly hydrogen-bonded dimer, with low energy barriers to other structures, revealing key insights into aminoxyl chemistry.

More Related Videos

Application of Genetically Encoded Fluorescent Nitric Oxide (NO•) Probes, the geNOps, for Real-time Imaging of NO• Signals in Single Cells

Application of Genetically Encoded Fluorescent Nitric Oxide (NO•) Probes, the geNOps, for Real-time Imaging of NO• Signals in Single Cells

Published on: March 16, 2017

Analytical Techniques for Assaying Nitric Oxide Bioactivity

Analytical Techniques for Assaying Nitric Oxide Bioactivity

Published on: June 18, 2012

Related Experiment Videos

Last Updated: Mar 26, 2026

Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds

Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds

Published on: February 16, 2022

Application of Genetically Encoded Fluorescent Nitric Oxide (NO•) Probes, the geNOps, for Real-time Imaging of NO• Signals in Single Cells

Application of Genetically Encoded Fluorescent Nitric Oxide (NO•) Probes, the geNOps, for Real-time Imaging of NO• Signals in Single Cells

Published on: March 16, 2017

Analytical Techniques for Assaying Nitric Oxide Bioactivity

Analytical Techniques for Assaying Nitric Oxide Bioactivity

Published on: June 18, 2012

Area of Science:

Theoretical Chemistry
Physical Chemistry
Free Radical Chemistry

Background:

Aminoxyls are kinetically persistent free radicals.
H2NO serves as the foundational model for aminoxyls.
Understanding H2NO's reactivity is crucial for aminoxyl chemistry.

Purpose of the Study:

To investigate the dimerization and reaction pathways of the H2NO radical.
To characterize the potential energy surface of H2NO dimers.
To elucidate the structural and electronic properties of H2NO dimeric forms.

Main Methods:

Computational chemistry methods were employed.
The potential energy surface for H2NO dimerization was explored.
Electronic structure calculations were performed on various dimeric isomers.

Main Results:

A metastable O-O bound dimer and several locally bound structures were identified.
A characteristic O-N-O-N ring structure, relevant to solid-state aminoxyls, was found.
The most stable dimer is a strongly hydrogen-bonded diradical, with low energy barriers to other isomers.

Conclusions:

H2NO dimerization yields a variety of structures, including a stable hydrogen-bonded dimer.
The binding of H2NO dimers results from a balance between electron repulsions and attractive interactions.
The findings provide a fundamental understanding of aminoxyl radical behavior and stability.