Chaykovsky

The Corey-Chaykovsky reaction entails the reaction of a sulfur ylide, either dimethylsulfoxonium methylide (1, Corey s ylide, sometimes known as DMSY) or dimethylsulfonium methylide (2), with electrophile 3 such as carbonyl, olefin, imine, or thiocarbonyl, to offer 4 as the corresponding epoxide, cyclopropane, aziridine, or thiirane. ... 

In 1962, Corey and Chaykovsky described the generation and synthetic utility of... 

Similar to phosphur ylides, sulfur ylides 1 and 2 possess the nucleophilic site at the carbon atom and the pendant leaving group at the heteroatom (sulfur). Different from the Wittig reaction, the Corey-Chaykovsky reaction does not lead to olefins. 

Epoxidation of aldehydes and ketones is the most profound utility of the Corey-Chaykovsky reaction. As noted in section 1.1.1, for an a,P-unsaturated carbonyl compound, 1 adds preferentially to the olefin to provide the cyclopropane derivative. On the other hand, the more reactive 2 generally undergoes the methylene transfer to the carbonyl, giving rise to the corresponding epoxide. For instance, treatment of P-ionone (26) with 2, derived from trimethylsulfonium chloride and NaOH in the presence of a phase-transfer catalyst Et4BnNCl, gave rise to vinyl epoxide 27 exclusively. ... 

Isolated carbonyls always give epoxides from the Corey-Chaykovsky reaction. Take the aldehyde substrate as an example. Spiro epoxide 30 was produced from the reaction of trisnorsqualene aldehyde 28 (R20 represents the polyene side-chain with 20 carbons) with substituted sulfur ylide 29, prepared in situ from cyclopropyldiphenylsulfonium tetrafluoroborate and KOH. " For the epoxidation of ketones, the Corey-Chaykovsky reaction works well for diaryl- (31), arylalkyl- (32), ... 

The Corey-Chaykovsky reaction incited some applications in medicinal chemistry. During the synthesis of analogs of fluconazole, an azole antifungal agent, treatment of 49 with 1 led to the corresponding epoxide, which was subsequently... 

In the initial report by Corey and Chaykovsky, dimethylsulfonium methylide (2) reacted smoothly with benzalaniline to provide an entry to 1,2-diphenylaziridine 67. Franzen and Driesen reported the same reaction with 81% yield for 67. In another example, benzylidene-phenylamine reacted with 2 to produce l-(p-methoxyphenyl)-2-phenylaziridine in 71% yield. The same reaction was also carried out using phase-transfer catalysis conditions.Thus aziridine 68 could be generated consistently in good yield (80-94%). Recently, more complex sulfur ylides have been employed to make more functionalized aziridines, as depicted by the reaction between A -sulfonylimine 69 with diphenylsulfonium 3-(trimethylsilyl)propargylide (70) to afford aziridine 71, along with desilylated aziridine 72. ... 

In Corey and Chaykovsky s initial investigation, a cyclic ylide 79 was observed from the reaction of ethyl cinnamate with ylide 1 in addition to 32% of cyclopropane 53. In a similar fashion, an intermolecular cycloaddition between 2-acyl-3,3-bis(methylthio)acrylnitrile 80 and 1 furnished 1-methylthiabenzene 1-oxide 81. Similar cases are found in transformations of ynone 82 to 1-arylthiabenzene 1-oxide 83 and N-cyanoimidate 84 to adduct ylide 85, which was subsequently transformed to 1-methyl-lX -4-thiazin-l-oxide 86. ... 

In addition to the synthesis of heterocycles, the Corey-Chaykovsky reaction bestows an entry to carbocycles as well. The reaction of (trialkylsilyl)vinylketene 89 with substituted ylide 90 led exclusively to rrans-4,5-dimethyl cyclopentenone 91. The substituted ylide 90 here serves as a nucleophilic carbenoid reagent in the formal [4 +1] annulation reaction. 

Notably, some substrates possess enough steric bias to exert sterospecificity for the Bucherer-Bergs reaction. For instance, ketone 21, derived from enone 20 via a Corey-Chaykovsky reaction, underwent a Bucherer-Bergs reaction to fashion spirohydantoin 22 as a single isomer. 

It has been found that aryl groups can also be introduced into the a-position of sulphoxides. Corey and Chaykovsky have demonstrated that chlorobenzene reacts at room temperature with an excess of sodium methylsulphinyl carbanion to give methyl benzyl sulphoxide in 41% yield. The authors believe that a benzyne intermediate may be involved in the reaction400,401 (equation 174). 

Corey and Chaykovsky were the first to investigate the reaction of dimethyl sulphoxide anion (dimsyl anion) with aldehydes and ketones400,401. They found that the reaction with non-enolizable carbonyl compounds results in the formation of /1-hydroxyalkyl sulphoxides in good yields (e.g. Ph2CO—86%, PhCHO—50%). However, with enolizable carbonyl compounds, particularly with cycloalkanones, poor yields of hydroxyalkyl products are observed (e.g. camphor—28%, cyclohexanone—17%, but... 

Corey and Chaykovsky had discovered that dimethyl sulfoxide is converted to methyl-sulfinyl carbanion upon treatment with sodium hydride114 and that this conjugate base of DMSO reacts with various electrophiles115. This finding has opened up various reactions with a-sulfmyl carbanions derived from sulfoxides, since the sulfinyl function can be removed either by thermolysis or by subjecting the compound to reductive desulfurization. Thus a-sulfmyl carbanions have become versatile synthetically useful reagents. 

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