Johnson–Corey–Chaykovsky reaction

The Johnson–Corey–Chaykovsky reaction (sometimes referred to as the Corey–Chaykovsky reaction or CCR) is a <a href="/facts/Chemical_reaction/GpqWlKrz">chemical reaction</a> used in <a href="/facts/Organic_chemistry/djxhxaNg">organic chemistry</a> for the synthesis of <a href="/facts/Epoxide/PLxRI7r1">epoxides</a>, <a href="/facts/Aziridine/r89KuEYb">aziridines</a>, and <a href="/facts/Cyclopropane/BAUAYB7s">cyclopropanes</a>. It was discovered in 1961 by A. William Johnson and developed significantly by <a href="/facts/E._J._Corey/xsj35SIc">E. J. Corey</a> and Michael Chaykovsky. The reaction involves addition of a sulfur <a href="/facts/Ylide/WcfsUPR7">ylide</a> to a <a href="/facts/Ketone/BqQXpLo4">ketone</a>, <a href="/facts/Aldehyde/xSIRkW03">aldehyde</a>, <a href="/facts/Imine/yK72z07j">imine</a>, or <a href="/facts/Enone/gAflh5z4">enone</a> to produce the corresponding 3-membered ring. The reaction is <a href="/facts/Diastereoselective/ReBkFoCP">diastereoselective</a> favoring trans substitution in the product regardless of the initial <a href="/facts/Stereochemistry/XkcRVNwd">stereochemistry</a>. The synthesis of <a href="/facts/Epoxide/PLxRI7r1">epoxides</a> via this method serves as an important <a href="/facts/Retrosynthetic_analysis/PwP65DjN">retrosynthetic</a> alternative to the traditional <a href="/facts/Epoxidation/PLxRI7r1">epoxidation</a> reactions of <a href="/facts/Olefin/RtYcS6kU">olefins</a>.

The reaction is most often employed for epoxidation via <a href="/facts/Methylene_(compound)/vIPU9NXl">methylene</a> transfer, and to this end has been used in several notable <a href="/facts/Total_syntheses/3GGoqhBm">total syntheses</a> (See Synthesis of epoxides below). Additionally detailed below are the history, mechanism, scope, and enantioselective variants of the reaction. Several reviews have been published.

Johnson–Corey–Chaykovsky reaction open-in-new

Johnson–Corey–Chaykovsky reaction