Comparison With Other Methods
Analogous sulfoxide eliminations are generally harder to implement than selenoxide eliminations. Formation of the carbon–sulfur bond is usually accomplished with highly reactive sulfenyl chlorides, which must be prepared for immediate use. However, sulfoxides are more stable than the corresponding selenoxides, and elimination is usually carried out as a distinct operation. This allows thermolysis conditions to be optimized (although the high temperatures required may cause other thermal processes). In addition, sulfoxides may be carried through multiple synthetic steps before elimination is carried out.
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The combination of silyl enol ethers with palladium(II) acetate (Pd(OAc)2), the Saegusa oxidation, gives enones. However, the reaction requires stoichiometric amounts of Pd(OAc)2 and thus is not amenable to large-scale synthesis. Catalytic variants have been developed.
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For β-dicarbonyl compounds, DDQ can be used as an oxidizing agent in the synthesis of enediones. Additionally, some specialized systems give better yields upon DDQ oxidation.
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Read more about this topic: Selenoxide Elimination
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