Ozonolysis
Ozonolysis - Related Videos
06:52
Ozonolysis of Alkenes
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2023
Source: Vy M. Dong and Zhiwei Chen, Department of Chemistry, University of California, Irvine, CA This experiment will demonstrate an example of an ozonolysis reaction to synthesize vanillin from isoeugenol (Figure 1). Ozonolysis of alkenes, an oxidation reaction between ozone and an alkene, is a common method to prepare aldehydes, ketones, and carboxylic acids. This experiment also demonstrates the use of an ozone generator and a low temperature (−78 °C) reaction. Figure 1. Diagram showing...
08:33
Functionalization and Dispersion of Carbon Nanomaterials Using an Environmentally Friendly Ultrasonicated Ozonolysis Process
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Cited by 11 •
2017
Here, a novel method for the functionalization and stable dispersion of carbon nanomaterials in aqueous environments is described. Ozone is injected directly into an aqueous dispersion of carbon nanomaterial that is continuously recirculated through a high-powered ultrasonic cell.
01:46
Oxidative Cleavage of Alkenes: Ozonolysis
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2023
In ozonolysis, ozone is used to cleave a carbon–carbon double bond to form aldehydes and ketones, or carboxylic acids, depending on the work-up. Ozone is a symmetrical bent molecule stabilized by a resonance structure. Ozonolysis proceeds through an oxidative cleavage reaction. The first step is the electrophilic addition of ozone across the alkene double bond, forming an unstable molozonide intermediate, which reacts further to form a carbonyl and a carbonyl oxide. These intermediates...
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The alkene first reacts with ozone to form an unstable molozonide. This intermediate then rearranges into an ozonide, marking the key sequence before product-forming workup. Following this pathway explains why the original carbon–carbon double bond is converted into smaller oxygen-containing molecules and provides a mechanistic basis for the reaction’s predictable cleavage pattern.
The workup controls the oxidation state of the cleavage products. A reductive workup produces aldehydes or ketones, whereas an oxidative workup can convert suitable cleavage products into carboxylic acids. This distinction makes the reaction more than a simple bond-breaking step because the chosen follow-up treatment determines the functional groups ultimately isolated.
Cleavage occurs at the carbon–carbon double bond, separating the original structure into smaller oxygen-containing fragments. By examining whether the products are aldehydes, ketones, or carboxylic acids, chemists can work backward to infer where the unsaturation was located. The resulting product pattern therefore provides structural evidence rather than merely confirming that a reaction occurred.
The transformation follows a defined sequence: ozone adds across the carbon–carbon multiple bond, the initial molozonide rearranges into an ozonide, and a subsequent workup converts that intermediate into the desired oxygen-containing products. Selecting either reductive or oxidative treatment is the critical procedural decision because it determines whether aldehydes, ketones, or carboxylic acids result.
Ozonolysis is useful when a chemist needs either to prepare carbonyl compounds or to determine the location of unsaturation in an organic structure. Its predictable bond-breaking pattern supports both goals: synthesis benefits from access to aldehydes and ketones, while analysis benefits from interpreting the smaller products formed after cleavage.
The sequence from ozone addition to molozonide formation, ozonide rearrangement, and final workup illustrates how identifiable intermediates lead to different products. Studying this progression connects molecular-level changes with the observed aldehydes, ketones, or carboxylic acids. In this way, ozonolysis serves as both a synthetic reaction and a model for examining organic reaction pathways.