Depto. Química Orgánica

OXIDATION OF ALKENES

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15/07/2017
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The carbons of olefins are in a relatively low oxidation state and they can thus be transformed in other more oxidized substances. Olefin oxidation can be carried out gently or vigorously, with different outcome.
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Gentle Oxidation
Baeyer Test (cold diluted solution of potassium permanganate):
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Vigorous Oxidation (Ozonolysis)
The reaction of ozone with a given olefin goes through a complicated mechanism that implies a very important type of reaction in organic chemistry, the so-called 1,3-dipolar cycloaddition, as a consequence of ozone's electronic structure:
Image Comparison between the size and shape of ozone and oxygen.
The ozone molecule has an angular structure whose angle is in between those of sp3 and sp2 hybridizations.
This fact is explained by ozone's resonant forms that also indicate the charge separation between both ends of the molecule.
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The decomposition of the ozonide renders more or less oxidized products depending on the used co-reagent:
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