Corey–Kim oxidation

Corey–Kim Oxidation is a chemical reaction utilized in organic chemistry for the oxidation of primary and secondary alcohols to aldehydes, ketones, and related compounds using chloramine-T and dimethyl sulfoxide (DMSO) as reagents. Named after its developers, Elias James Corey and Choung Un Kim, who first reported the method in 1972, this oxidation process is notable for its mild reaction conditions and broad substrate applicability.

Reaction Mechanism

The Corey–Kim oxidation involves a unique mechanism that starts with the formation of an electrophilic chlorine species from chloramine-T. This species then reacts with DMSO to form an activated sulfoxide intermediate. The alcohol substrate interacts with this intermediate, leading to the formation of an alkoxysulfonium ion, which, upon elimination, yields the oxidized product and dimethyl sulfide as a byproduct.

Applications

The Corey–Kim oxidation is widely applied in synthetic organic chemistry due to its ability to selectively oxidize sensitive alcohols in the presence of other functional groups that might be susceptible to oxidation under harsher conditions. It has been employed in the synthesis of complex natural products and pharmaceuticals, where selective oxidation is crucial.

Advantages and Limitations

One of the main advantages of the Corey–Kim oxidation is its mildness, making it suitable for substrates that are sensitive to strong oxidizing agents. However, the reaction's reliance on chloramine-T, a toxic and potentially explosive reagent, poses certain safety and environmental concerns. Additionally, the generation of dimethyl sulfide, a malodorous byproduct, can be considered a drawback in some settings.

Comparison with Other Oxidation Methods

The Corey–Kim oxidation is often compared to other oxidation techniques such as the Swern oxidation, PCC oxidation, and Dess-Martin periodinane oxidation. Each method has its unique features, reagents, and conditions, making them suitable for different types of substrates and desired outcomes. The choice between these methods depends on factors such as the sensitivity of the substrate, the tolerance of other functional groups present, and the specific requirements of the reaction conditions.

See Also

• Oxidation reactions
• Swern oxidation
• PCC oxidation
• Dess-Martin periodinane oxidation
• Organic synthesis