Imide-Catalyzed Oxidation System: Sulfides to Sulfoxides and Sulfones

Abstract

A new combination system, the oxidation of sulfides using aqueous NaOCl in the presence of a catalytic amount of imide under two-phase conditions, has been developed. The combination effectively converts various sulfides to the corresponding sulfoxides and sulfones. It was deduced that the imide could react with NaOCl to produce N-chloroimide, which would play roles of both the active oxidizing reagent and phase transfer catalyst.

Solventless Synthesis of Quaterphenyls and Terphenyls from Chalcones and Allylsulfones under Phase Transfer Catalysis Conditions

“…The crude product was purified through a small silica plug (AcOEt/PE = 1:1) to give 5.36 g of the title compound (78% yield). The analytical data match those reported in the literature [30].…”

Organic oxidations promoted in vortex driven thin films under continuous flow

“…38,39 This outcome was quite reasonably attributed to the low miscibility of the polar hypochlorite salts and the hydrophobic allyl phenyl sulfide, which prompted the development of various phase transfer catalysts to provoke this two phase reaction. 38,39 As allyl sulfides and their corresponding sulfoxides and sulfones are highly useful in synthesis, [40][41][42][43][44][45] we were curious as to whether or not the intense micro-mixing in the VFD would enable oxidation of organic sulfides in bleach without recourse to organic solvents, surfactants or phase transfer catalysts. First, allyl phenyl sulfide (3) was reacted directly with 10 and 20 equivalents of bleach oxidant in batch mode, where the mixture was simply stirred with a stirring bar for 40 minutes at room temperature.…”

“…The formation of 6 was somewhat surprising, as this material has not been previously observed in the bleach oxidation of allyl phenyl sulfide. 38,39,46 It is likely that the chlorination results from deprotonation of the acidic α protons of allyl phenyl sulfone (the pH of the bleach was 12), followed by direct reaction with an electrophilic chlorine species such as hypochlorous acid. This pathway is consistent with that observed in the α-chlorination of other Scheme 2 A. Allyl phenyl sulfide (3) is immiscible in bleach.…”

7.28 Oxidation of Sulfur, Selenium, and Tellurium

“…In order to achieve this goal, reaction conditions have been tuned by using an excess of the oxygen source, prolonging the reaction time, or working at higher reaction temperatures in order to facilitate the second oxidation of sulfoxides to sulfones. Some of the oxidative systems used for the oxidation of sulfides to sulfones have been highlighted in the previous section: H 2 199 NaOCl, 222,223 and others. 165,195,230,244 The oxidation rate of sulfoxides to sulfones with peroxy acids is lower than that of sulfides to sulfoxides as the former are less nucleophilic species than sulfides.…”