4.02 – Functions Incorporating a Halogen and a Chalcogen

摘要: The most frequently reported compounds containing a tetracoordinated carbon bearing halogen and chalcogen are α-haloethers, -sulfides, -sulfones, -sulfoxides -selenides, α-haloalkyl esters. Although many of these have limited stability, they useful synthetic intermediates because this there has been high level interest in their preparation use since 1995. This is particularly true α-fluoroethers sulfides, which prepared using not only the extensive range chemical fluorinating agents now available, but increasingly electrochemical methods. More generally, commercial importance perfluorinated partially fluorinated ethers, fact that glycosyl halides continue to be important carbohydrate chemistry, contributes frequency with functional group encountered literature. α-halosulfoxides sulfones almost invariably begins sulfide involves an oxidation–chlorination sequence or reverse. Irrespective actual used, reagent choice for oxidation step currently MCPBA. both approaches used α-fluoro compounds, α-chloro analogs always chlorination NCS followed by MCPBA oxidation, as one-pot procedure. facility α-carbanions can produced from importance. methods prepare α-haloselenides mirror those corresponding involving lighter chalcogens. α-Halotellurides related quite unstable little new work area.