A Facile and Selective Procedure for Oxidation of Sulfides to Sulfoxides on Silica Gel Supported Magnesium Monoperoxyphthalate (MMPP) in Dichloromethane
作者:Mohammed Hashmat Ali、William C. Stevens
DOI:10.1055/s-1997-1420
日期:1997.7
The scope of the magnesium monoperoxyphthalate (MMPP) oxidation of sulfides to sulfoxides has been extended by using hydrated silica gel as a solid support in dichloromethane media. This procedure works in the presence of a number of functional groups on the sulfides, including carbonyl and alkene groups that have been known to undergo Baeyer-Villiger oxidation and epoxidation with MMPP when using more conventional procedures. To our knowledge, this is the first example of oxidation of sulfides containing a carbonyl group with MMPP in non-aqueous media without any Baeyer-Villiger reaction. The reported procedure is easy to perform, product separation is trivial and it produces excellent yields.
Abstract An efficient and highly selective procedure for oxidation of sulfides to sulfoxides with N‐bromosuccinimide (NBS) in the presence of hydrated silica gel has been developed. Hydrated silica gel supplies the water necessary for decomposition of the intermediate bromosulfonium salt to the product, allowing the reaction to employ a nonaqueous media. Also, this procedure has increased the scope
Generation of the<i>α</i>-Sulfinyl Carbenoid from<i>α</i>-Chloro Sulfoxides: A New Method for One-Carbon Homologation of Ketones to<i>α</i>-Sulfinyl Ketones
carbenoids were successfully used in a new method for homologation of ketones to α-sulfinyl ketones. Treatment of the carbanion of chloromethyl phenyl sulfoxide with ketones gave the adducts, α-chloro β-hydroxy sulfoxides, in nearly quantitative yields. The adducts were treated with excess lithium diisopropylamide to give one-carbon homologated α-sulfinyl ketones via α-sulfinyl β-oxido carbenoids in moderate
Addition of the carbanion of chloromethylphenylsulfoxide to ketones gave the adducts, which were treated with lithium diisopropylamide to afford one-carbon homologated α-sulfinyl ketones via α-sulfinyl carbenoids in moderate to high yields.
A facile and efficient protocol for the α-benzoyloxylation of β-keto sulfides is presented. This methodology provides a step-economical, mild and practical access to highly functionalized α-O-benzoyloxy substituted β-keto sulfides, including those with quaternary carbons, which are not easily obtained through currently available methods.