| Corey-Kim oxidation | |
|---|---|
| Named after | Elias James Corey Choung Un Kim |
| Reaction type | Organic redox reaction |
| Identifiers | |
| Organic Chemistry Portal | corey-kim-oxidation |
TheCorey–Kim oxidation is anoxidation reaction used to synthesizealdehydes andketones from primary and secondaryalcohols.[1][2][3][4][5] It is named for American chemist and Nobel LaureateElias James Corey and Korean-American chemistChoung Un Kim.
Although the Corey–Kim oxidation possesses the distinctive advantage overSwern oxidation of allowing an operation above –25 °C, it is not so commonly used due to issues with selectivity in substrates susceptible to chlorination byN-chlorosuccinimide.
Dimethyl sulfide (Me2S) is treated withN-chlorosuccinimide (NCS), resulting in formation of an "active DMSO" species that is used for the activation of the alcohol. Addition oftriethylamine to the activated alcohol leads to its oxidation to aldehyde or ketone and generation of dimethyl sulfide. In variance with other alcohol oxidation using "activated DMSO," the reactive oxidizing species is not generated by reaction of DMSO with an electrophile. Rather, it is formed by oxidation of dimethyl sulfide with an oxidant (NCS).
Under Corey–Kim conditionsallylic andbenzylicalcohols have a tendency to evolve to the corresponding allyl and benzyl chlorides unless the alcohol activation is very quickly followed by addition oftriethylamine. In fact, Corey–Kim conditions —with no addition of triethylamine— are very efficient for the transformation of allylic and benzylic alcohols to chlorides in presence of other alcohols.
Substituting dimethyl sulfide with something less noxious has been the goal of several research projects. Ohsugiaet al.[6] substituted a long-chain sulfide, dodecyl methyl sulfide, for dimethyl sulfide. Crichet al.[7] utilized fluorous technology in a similar manner.