FACTOID # 16: In the 2000 Presidential Election, Texas gave Ralph Nader the 3rd highest popular vote count of any US state.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Ozonolysis

In ozonolysis ozone cleaves an alkene into carbonyl compounds. Ozone (O3) is an allotrope of oxygen, the molecule consisting of three oxygen atoms instead of the more stable diatomic O2. ... An alkene is an unsaturated hydrocarbon containing at least one carbon-carbon double bond. ... In chemistry, a carbonyl group is a functional group composed of an atom of carbon double-bonded to an atom of oxygen. ...


The ozonolysis process can be expressed this way:


RCH=CR'2 + O3RC(H)=O + O=CR'2 An alkene is an unsaturated hydrocarbon containing at least one carbon-carbon double bond. ... Ozone (O3) is an allotrope of oxygen, the molecule consisting of three oxygen atoms instead of the more stable diatomic O2. ... kjhfckjdsvsdv ... A ketone is either the functional group characterized by a carbonyl group linked to two other carbon atoms or a compound that contains this functional group. ...


First the alkene reacts with ozone to form an intermediate ozonide which is hydrolysed to form two carbonyl compounds. These will be aldehydes or ketones depending on the structure of the initial alkene. A reducing agent like zinc or dimethyl sulfide is present to reduce hydrogen peroxide that is liberated as a side-product and that would otherwise give secondary oxidation reactions. An alkene is an unsaturated hydrocarbon containing at least one carbon-carbon double bond. ... Ozone (O3) is an allotrope of oxygen, the molecule consisting of three oxygen atoms instead of the more stable diatomic O2. ... Hydrolysis is a chemical process in which a molecule is cleaved into two parts by the addition of a molecule of water. ... In chemistry, a carbonyl group is a functional group composed of an atom of carbon double-bonded to an atom of oxygen. ... kjhfckjdsvsdv ... A ketone is either the functional group characterized by a carbonyl group linked to two other carbon atoms or a compound that contains this functional group. ... A reducing agent is a substance used in electrochemistry that reduces another substance. ... General Name, Symbol, Number zinc, Zn, 30 Chemical series transition metals Group, Period, Block 12, 4, d Appearance bluish pale gray Atomic mass 65. ... Dimethyl sulfide causes that distinctive smell from your St. ... Hydrogen peroxide (H2O2) is a clear liquid, a little more viscous than water, that has strong oxidizing properties and is therefore a powerful bleaching agent that has found use as a disinfectant and (in high concentrations as high test peroxide) as an oxidizer or monopropellant in rockets. ...


The ozonide can be reduced with lithium aluminium hydride to the corresponding alcohols. Ozonolytic reaction can also be conducted in an oxidizing environment, which generates carboxylic acids and ketones instead of aldehydes and ketones. Lithium Aluminium Hydride (LiAlH4), commonly abbreviated to LAH, is a powerful reducing agent used in organic chemistry. ... In general usage, alcohol (from Arabic al-khwl الكحول, or al-ghawl الغول) refers almost always to ethanol, also known as grain alcohol, and often to any beverage that contains ethanol (see alcoholic beverage). ... Structure of a carboxylic acid Carboxylic acids are organic acids characterized by the presence of a carboxyl group, which has the formula -C(=O)-OH, usually written as COOH. The salts and anions of carboxylic acids are called carboxylates generally. ...


Ozonolysis was invented by Christian Friedrich Schönbein in 1840 and in the early days of chemistry it was an important tool in organic structure elucidation. Ozonolysis of an unknown alkene yields smaller carbonyl fragments easier to identify and from which the structure of the original alkene could be derived. An ozonolysis mechanism was first proposed by Rudolf Criegee in 1953. Christian Friedrich Schönbein (October 18, 1799 – August 29, 1868) was a German-Swiss chemist who is most well-known for his discovery of guncotton. ... Rudolf Criegee (1902-1975) was a German chemist. ...


Image:Ozonolysis.png Image File history File links ozonolysis mechanism File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...



Ozone reacts with an alkene in a 1,3-dipolar cycloaddition to a molozonide which is a 5 membered ring structure with 3 neighboring oxygen atoms (a 1,2,3-trioxolane). This intermediate is unstable and one oxygen to oxygen bond is broken by heterolysis to form a zwitterion and then the carbon to carbon bond splits with formation of a carbonyl compound and a second zwitterion. In the third reaction step the carbonyl compound and the zwitterion recombine in a second cycloaddition to form the ozonide which is also a five membered ring but with 2 neighboring oxygen atoms (peroxide bond) and the third inserted in the original carbon carbon double bond as an ether linkage (a 1,2,4-trioxolane). Evidence for this mechanism is found in isotopic labeling 1. Benzaldehyde labeled with 17oxygen reacts with the zwitterionic intermediate in an ozonolysis reaction and the isotope ends up exclusively in the ether linkage of the ozonide. The 1,3-dipolar cycloaddition is an organic chemical reaction (specifically, a cycloaddition) between a 1,3-dipole and a substituted alkene to form a substituted five-membered ring. ... In chemistry, heterolysis is chemical bond cleavage of a neutral molecule generating a cation and an anion. ... A zwitterion (from German Zwitter — hybrid, hermaphrodite) is a compound with acidic and basic groups in the same molecule. ... Ether is the general name for a class of chemical compounds which contain an ether group — an oxygen atom connected to two (substituted) alkyl groups. ... Isotopic labeling is a technique for tracking the passage of a sample of substance through a system. ... The chemical compound benzaldehyde (C6H5CHO) consists of a benzene ring with an aldehyde group attached to one carbon. ...


There is still dispute over whether the molozonide collapses via a concerted or radical process; this may also exhibit a substrate dependence.


In industry azelaic acid and pelargonic acids are produced from ozonolysis of oleic acid. Oleic acid is a monounsaturated fatty acid found in various animal and vegetable sources. ...


External links

University of Maryland, College Park The University of Maryland, College Park (also known as UM, UMD, or UMCP) is a public coeducational university situated in suburban College Park, Maryland just outside Washington, D.C. The flagship institution of the University System of Maryland, the university is most often referred to... Phenanthrene is a polycyclic aromatic hydrocarbon composed of three fused benzene rings--as the above formula shows. ... Organic Syntheses is a scientific journal that Since 1921 has provided the chemistry community with annual collections of detailed and checked procedures for the organic synthesis of organic compounds. ... Cyclohexene is a hydrocarbon and cyclic alkene. ... Organic Syntheses is a scientific journal that Since 1921 has provided the chemistry community with annual collections of detailed and checked procedures for the organic synthesis of organic compounds. ... Organic Syntheses is a scientific journal that Since 1921 has provided the chemistry community with annual collections of detailed and checked procedures for the organic synthesis of organic compounds. ...

References

  • 1 The Mechanism of Ozonolysis Revisited by 17O-NMR Spectroscopy Christian Geletneky, Stefan Berger European Journal of Organic Chemistry Volume 1998, Issue 8 , Pages 1625 - 1627 Abstract

  Results from FactBites:
 
ozonolysis (0 words)
Ozonolysis is used as a synthetic route to carbonyl compounds.
Ozonolysis is also used to locate the position of double bonds in unknown molecules.
Muscalure is the pheromone released by female house flies to attract males.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m