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

1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview01:26

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 water loss...
Nitrosation of Enols01:19

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 NaNO201:20

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.
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism01:37

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.
Resonance02:52

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.
Structures of Carboxylic Acid Derivatives01:28

Structures of Carboxylic Acid Derivatives

Structure of Carboxylic Acid Derivatives
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...

You might also read

Related Articles

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

Sort by
Same author

Introducing the 2026 Early Career Board of <i>ACS Medicinal Chemistry Letters</i>.

ACS medicinal chemistry letters·2026
Same author

On the mechanisms of the use of nitroxide as antioxidant for ultra high molecular weight polyethylene.

International journal of radiation biology·2026
Same author

Cyclic Hydroxylamines as Monitors of Peroxynitrite and Superoxide-Revisited.

Antioxidants (Basel, Switzerland)·2022
Same author

The nitroxide/antioxidant 3-carbamoyl proxyl attenuates disease severity in murine models of severe asthma.

Free radical biology & medicine·2021
Same author

3-Carbamoyl-proxyl nitroxide radicals attenuate bleomycin-induced pulmonary fibrosis in mice.

Free radical biology & medicine·2021
Same author

Sibling Adjustment to Childhood Chronic Illness: An Integrative Review.

Journal of family nursing·2020

Related Experiment Video

Updated: Jun 12, 2026

Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds
08:23

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

Published on: February 16, 2022

On the distinction between nitroxyl and nitric oxide using nitronyl nitroxides.

Uri Samuni1, Yuval Samuni, Sara Goldstein

  • 1Department of Chemistry and Biochemistry, Queens College, City University of New York, Flushing, New York 11367, USA.

Journal of the American Chemical Society
|May 28, 2010
PubMed
Summary

Nitric oxide (NO) detection using nitronyl nitroxides is complicated by nitric oxide (HNO) which reacts to form hydroxylamines. Nitronyl nitroxides can distinguish NO from HNO only at low concentrations.

More Related Videos

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones
07:30

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones

Published on: January 21, 2020

Analytical Techniques for Assaying Nitric Oxide Bioactivity
11:28

Analytical Techniques for Assaying Nitric Oxide Bioactivity

Published on: June 18, 2012

Related Experiment Videos

Last Updated: Jun 12, 2026

Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds
08:23

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

Published on: February 16, 2022

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones
07:30

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones

Published on: January 21, 2020

Analytical Techniques for Assaying Nitric Oxide Bioactivity
11:28

Analytical Techniques for Assaying Nitric Oxide Bioactivity

Published on: June 18, 2012

Area of Science:

  • Biochemistry
  • Chemical Biology
  • Physiology

Background:

  • Accurate detection of nitric oxide (NO) and nitrosyl hydride (HNO) is crucial for understanding their biological roles.
  • Nitronyl nitroxides, like C-PTIO, are commonly used to detect NO via its reaction forming imino nitroxides.

Purpose of the Study:

  • To investigate the reaction mechanism between HNO and nitronyl nitroxides.
  • To determine the rate constant for the reaction of HNO with C-PTIO.
  • To assess the potential of nitronyl nitroxides to differentiate between NO and HNO.

Main Methods:

  • Utilized Angeli's salt (AS) as an HNO donor.
  • Employed metmyoglobin as a competing agent to quantify reaction rates.
  • Spectroscopic analysis to identify reaction products.

Main Results:

  • HNO readily reacts with nitronyl nitroxides (e.g., C-PTIO, PTIO) forming imino nitroxides and hydroxylamines.
  • The rate constant for C-PTIO reduction by HNO was determined to be (1.4 ± 0.2) x 10^5 M^-1 s^-1 at pH 7.0.
  • Complete conversion to imino hydroxylamine occurs at higher AS to nitronyl nitroxide ratios.

Conclusions:

  • Nitronyl nitroxides are reduced by HNO to hydroxylamines and subsequently converted to imino nitroxides and imino hydroxylamines.
  • The reaction pathway allows for discrimination between NO and HNO only when nitronyl nitroxide concentration is significantly lower than HNO production.