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'''Jones Oxidation''' is a powerful organic chemistry reaction used to oxidize primary and secondary alcohols to aldehydes and ketones, respectively, using chromic trioxide ([[CrO3]]) in diluted sulfuric acid ([[H2SO4]]). This reaction is notable for its high efficiency and selectivity in the presence of other functional groups, making it a valuable tool in the synthesis of various organic compounds.
{{DISPLAYTITLE:Jones Oxidation}}


==Mechanism==
== Jones Oxidation ==
The Jones oxidation mechanism involves the formation of a chromic acid ([[H2CrO4]]) intermediate from [[CrO3]] and [[H2SO4]]. This chromic acid then reacts with the alcohol to form a chromate ester, which undergoes a series of rearrangements and eliminations to yield the oxidized product (aldehyde or ketone) and a Cr(III) species as a byproduct.


==Applications==
[[File:Jones_Oxidation_Scheme.png|thumb|right|300px|Schematic representation of the Jones oxidation.]]
Jones oxidation is widely used in organic synthesis for the preparation of aldehydes and ketones from primary and secondary alcohols, respectively. It is particularly useful in the synthesis of complex molecules in the pharmaceutical and fine chemical industries due to its high selectivity and efficiency.


==Advantages and Limitations==
The '''Jones oxidation''' is a chemical reaction used to oxidize [[primary alcohol]]s to [[carboxylic acid]]s and [[secondary alcohol]]s to [[ketone]]s. This reaction is named after Sir [[Ewart Jones]], who developed the method. The Jones oxidation is a powerful and widely used method in organic chemistry for the transformation of alcohols into more oxidized functional groups.
One of the main advantages of Jones oxidation is its ability to selectively oxidize alcohols in the presence of other sensitive functional groups. However, the reaction conditions are acidic and can lead to side reactions or degradation of acid-sensitive substrates. Additionally, the use of toxic chromium(VI) compounds raises environmental and safety concerns.


==Environmental Considerations==
== Mechanism ==
Due to the toxic nature of chromium(VI) compounds used in Jones oxidation, alternative methods have been developed to reduce or eliminate the environmental impact. These include the use of less toxic oxidizing agents and the development of catalytic systems that minimize the use of hazardous materials.


==See Also==
The Jones oxidation involves the use of [[chromium trioxide]] (CrO_) in the presence of [[sulfuric acid]] (H_SO_) and [[acetone]] as a solvent. The reaction proceeds through the formation of a chromate ester intermediate, which undergoes a series of redox reactions to yield the oxidized product.
* [[Oxidation reactions]]
* [[Organic synthesis]]
* [[Chromic acid]]
* [[Aldehyde]]
* [[Ketone]]


==References==
=== Step 1: Formation of Chromate Ester ===
<references/>
 
In the first step, the alcohol reacts with chromium trioxide in the presence of sulfuric acid to form a chromate ester. This step is crucial as it activates the alcohol for further oxidation.
 
=== Step 2: Redox Reaction ===
 
The chromate ester undergoes a redox reaction, where the chromium is reduced from the +6 oxidation state to the +3 oxidation state, and the alcohol is oxidized to the corresponding carbonyl compound. For primary alcohols, this results in the formation of carboxylic acids, while secondary alcohols are converted to ketones.
 
== Applications ==
 
The Jones oxidation is particularly useful in synthetic organic chemistry for the preparation of carboxylic acids and ketones from alcohols. It is often employed in the synthesis of complex molecules where selective oxidation is required.
 
== Limitations ==
 
One of the main limitations of the Jones oxidation is its use of toxic chromium compounds, which pose environmental and safety concerns. Additionally, the reaction is not suitable for substrates that are sensitive to acidic conditions or that contain other functional groups that may be oxidized under the reaction conditions.
 
== Related Pages ==
 
* [[Oxidation (chemistry)]]
* [[Alcohol oxidation]]
* [[Chromium trioxide]]
* [[Ewart Jones]]


[[Category:Organic reactions]]
[[Category:Organic reactions]]
[[Category:Oxidation reactions]]
[[Category:Oxidation reactions]]
{{Chemistry-stub}}

Latest revision as of 05:39, 16 February 2025


Jones Oxidation[edit]

Schematic representation of the Jones oxidation.

The Jones oxidation is a chemical reaction used to oxidize primary alcohols to carboxylic acids and secondary alcohols to ketones. This reaction is named after Sir Ewart Jones, who developed the method. The Jones oxidation is a powerful and widely used method in organic chemistry for the transformation of alcohols into more oxidized functional groups.

Mechanism[edit]

The Jones oxidation involves the use of chromium trioxide (CrO_) in the presence of sulfuric acid (H_SO_) and acetone as a solvent. The reaction proceeds through the formation of a chromate ester intermediate, which undergoes a series of redox reactions to yield the oxidized product.

Step 1: Formation of Chromate Ester[edit]

In the first step, the alcohol reacts with chromium trioxide in the presence of sulfuric acid to form a chromate ester. This step is crucial as it activates the alcohol for further oxidation.

Step 2: Redox Reaction[edit]

The chromate ester undergoes a redox reaction, where the chromium is reduced from the +6 oxidation state to the +3 oxidation state, and the alcohol is oxidized to the corresponding carbonyl compound. For primary alcohols, this results in the formation of carboxylic acids, while secondary alcohols are converted to ketones.

Applications[edit]

The Jones oxidation is particularly useful in synthetic organic chemistry for the preparation of carboxylic acids and ketones from alcohols. It is often employed in the synthesis of complex molecules where selective oxidation is required.

Limitations[edit]

One of the main limitations of the Jones oxidation is its use of toxic chromium compounds, which pose environmental and safety concerns. Additionally, the reaction is not suitable for substrates that are sensitive to acidic conditions or that contain other functional groups that may be oxidized under the reaction conditions.

Related Pages[edit]