Name: baeyer-villiger oxidation and product formation
Uploaded: 2023-04-30T10:19:32.000Z
Duration: 1 min 22 s
Channel: JoVE

Baeyer&#8211;Villiger oxidation uses peracid and an acid catalyst to convert aldehydes to carboxylic acids and ketones to esters via the insertion of an oxygen atom next to the carbonyl carbon.
The substrate&#39;s carbonyl oxygen is first protonated, which makes the carbonyl carbon more electrophilic.
A nucleophilic attack by the terminal oxygen of the peracid, followed by the loss of a proton, produces a tetrahedral intermediate.
Protonating the carboxylate facilitates a concerted intramolecular process wherein reformation of the carbonyl bond, migration of a group from carbon to oxygen, and cleavage of the weak O&#8211;O bond take place, releasing the final product.
With unsymmetrical ketones, a question that arises is which group undergoes migration? With two possible outcomes, one of the products predominates.
The reaction result depends on the migratory aptitude of different groups; thus, Baeyer&#8211;Villiger oxidations are regioselective. Also, note that the reaction retains the stereochemistry at the migrating center.
For aromatic substrates, an electron-donating group accelerates the migration process, while an electron-withdrawing group retards it.

reactions of aldehydes and ketones: baeyer&ndash;villiger oxidation

Reactions of Aldehydes and Ketones: Baeyer&ndash;Villiger Oxidation

Baeyer&#8211;Villiger oxidation converts aldehydes to carboxylic acids and ketones to esters. The reaction uses peroxy acids or peracids and is often catalyzed by acid. The reaction is named after its pioneers, Adolf von Baeyer and Victor Villiger. The reaction is achieved by a wide range of peracids such as m-chloroperoxybenzoic acid (mCPBA), perbenzoic acid (C6H5COOOH), peracetic acid (CH3COOOH), hydrogen peroxide (H2O2), and tert-butyl hydroperoxide (t-BuOOH).
The carbonyl center is activated by protonating the carbonyl oxygen. The peracid then adds across the C=O bond to give a tetrahedral intermediate called the Criegee intermediate. During the concerted intramolecular rearrangement that follows, the carbonyl group is restored, a group migrates from carbon to oxygen, and the weak peroxide bond cleaves to give an acid (if the substrate is an aldehyde) or an ester (if the substrate is a ketone).
<img alt="Acyl substitution reaction mechanism diagram, illustrating nucleophilic acyl attack and intermediate steps." src="/files/ftp_upload/12341/12341_PT_Figure_1.svg" style="text-align: center; height: 275px;" data-altupdatedat="1761830439000" data-alt="Figure1" />
The migratory aptitude of different groups follows the order of &#8211;H &#62; &#8211;CR3 &#62; &#8211;CHR2 &#38;approx; &#8211;Ph &#62; &#8211;CRH2 &#62; &#8211;&#38;NoBreak;CH3. This makes Baeyer&#8211;Villiger oxidation regioselective. Also, the reaction retains the stereochemistry at the migrating center for asymmetrical substrates. Reactions involving cyclic ketones produce lactones.

Baeyer&#8211;Villiger oxidation converts aldehydes to carboxylic acids and ketones to esters. The reaction uses peroxy acids or peracids and is often ...

reactions-of-aldehydes-and-ketones-baeyervilliger-oxidation

Education

JoVE Core

Organic Chemistry

Unit 1

Aldehydes and Ketones

KEY TERMS AND CONCEPTS

baeyer-villiger oxidation and product formation

Baeyer-Villiger oxidation changes aldehydes and ketones into new oxygen-containing products. Aldehydes are converted to carboxylic acids, and ketones are converted to esters. This reaction is often carried out with acid and a peroxy acid, also called a peracid.

Several oxidizing agents can be used for this reaction. Examples include m-chloroperoxybenzoic acid (mCPBA), perbenzoic acid (C6H5COOOH), peracetic acid (CH3COOOH), hydrogen peroxide (H2O2), and tert-butyl hydroperoxide (t-BuOOH). The reaction is named after Adolf von Baeyer and Victor Villiger, who first described it.

The carbonyl group is first activated by protonating the carbonyl oxygen. Then the peracid adds across the C=O bond to form a tetrahedral Criegee intermediate. In the next step, the molecule rearranges in a concerted process. The carbonyl group is restored, one group moves from carbon to oxygen, and the weak peroxide bond breaks.

This rearrangement gives an acid when the starting material is an aldehyde or an ester when the starting material is a ketone. The reaction is regioselective because different groups migrate in a set order. The migratory aptitude follows –H &gt; –CR3 &gt; –CHR2 ≈ –Ph &gt; –CRH2 &gt; –CH3. For asymmetrical substrates, the stereochemistry at the migrating center is retained. Cyclic ketones undergo this oxidation to form lactones.

Baeyer-Villiger Oxidation and Product Formation

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Aldehyde Tests and Oxidation to Carboxylic Acids

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Baeyer-Villiger oxidation changes aldehydes and ketones into new oxygen-containing products. Aldehydes are converted to carboxylic acids, and ketones are converted to esters. This reaction is often carried out with acid and a peroxy acid, also called a peracid. Several oxidizing agents can be used for this reaction. Examples include m-chloroperoxybenzoic acid (mCPBA), perbenzoic acid (C6H5COOOH), peracetic acid (CH3COOOH), hydrogen peroxide (H2O2), and tert-butyl hydroperoxide (t-BuOOH). The...

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key terms and concepts

Learn how Baeyer-Villiger oxidation turns aldehydes into carboxylic acids and ketones into esters through the Criegee intermediate and group migration.

Baeyer-Villiger Oxidation and Product Formation | JoVE K12

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Baeyer-Villiger Oxidation and Product Formation

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