Criegee oxidation

The Criegee oxidation is a <a href="/facts/Glycol_cleavage/fmQtKMzc">glycol cleavage</a> reaction in which <a href="/facts/Vicinal_difunctionalization/DJJgdHl5">vicinal</a> <a href="/facts/Diol/pmaVtfKx">diols</a> are <a href="/facts/Organic_oxidation/6DdmXG4S">oxidized</a> to form <a href="/facts/Ketone/BqQXpLo4">ketones</a> and <a href="/facts/Aldehyde/xSIRkW03">aldehydes</a> using <a href="/facts/Lead_tetraacetate/w18pPVlQ">lead tetraacetate</a>. It is analogous to the use of <a href="/facts/Periodate/y9IRt4t6">periodate</a> (<a href="/facts/Malaprade_reaction/EHCS5A4Q">Malaprade reaction</a>) but uses a milder <a href="/facts/Oxidant/1FQzB8pQ">oxidant</a>. This oxidation was discovered by <a href="/facts/Rudolf_Criegee/WQMmfnnh">Rudolf Criegee</a> and coworkers and first reported in 1931 using <a href="/facts/Ethylene_glycol/stFz6CVe">ethylene glycol</a> as the substrate.

The rate of the reaction is highly dependent on the relative geometric position of the two <a href="/facts/Hydroxyl_group/1Hs2QAEv">hydroxyl groups</a>, so much so that diols that are <a href="/facts/Cis%E2%80%93trans_isomerism/vqlchJly">cis</a> on certain rings can be reacted selectively as opposed to those that are trans on them. It was heavily stressed by Criegee that the reaction must be run in <a href="/facts/Anhydrous/A7B0fDLE">anhydrous</a> solvents, as any water present would hydrolyze the lead tetraacetate; however, subsequent publications have reported that if the rate of oxidation is faster than the rate of hydrolysis, the cleavage can be run in wet solvents or even aqueous solutions. For example, <a href="/facts/Glucose/oUSkoLCD">glucose</a>, <a href="/facts/Glycerol/sRQ6NBQQ">glycerol</a>, <a href="/facts/Mannitol/CeHJsKMq">mannitol</a>, and <a href="/facts/Xylose/MrboHHP9">xylose</a> can all undergo a Criegee oxidation in aqueous solutions, but <a href="/facts/Sucrose/7y1ke94L">sucrose</a> cannot.

Criegee oxidation open-in-new

Criegee oxidation