Dmso-promoted Hydroxysulfurization Reaction Of Several Electron-deficient Alkenes With High Chemoselectivity

β-Hydroxysulfide is an important structural molecule in the preparation of organic synthesis intermediates and the derivatization of natural product derivatization,and has great development potential.In the reported work,the hydroxysulfurization of olefins is an efficient method for the preparation ofβ-hydroxysulfides and their derivatives.The preparation strategy of electron-rich olefins in this type of method has been developed relatively maturely,but the hydroxysulfurization of electron-deficient olefins still has some challenges,such as in an oxygen atmosphere,the need for metal catalysts or reducing agents to inhibit the reaction to generate by-product of hydroxy sulfoxide,sulfone.Therefore,this paper focuses on the study of the electron-deficient olefin hydroxysulfation reaction of metal-free catalysts and reducing agents induced by oxygen in the air,which is mainly divided into the following two aspects:1.Usingα,β-unsaturated enamides and aryl thiophenols as raw materials,a highly chemoselective hydroxysulfurization reaction can be realized under mild reaction conditions.The suitability of the reaction substrates was investigated,and the results showed that a variety of arylthiophenols and electron-deficient alkenes showed good substrate tolerance.2.The practicability of this reaction was investigated,and the structural modification of the natural product estrone was also applicable to this method;theβ-hydroxysulfide synthesized by this method could be synthesized in a good yield by one simple oxidation.The cancer drug-bicalutamide shows that this method has good application value.Hypotheses for the reaction mechanism were put forward.A possible mechanism involved in the free radical reaction was explored through radical capture experiments and control experiments.The source of hydroxyl oxygen in the product was verified through¹⁸O isotope labeling experiments.In this paper,a mild and practical electron-deficient olefin difunctionalization reaction was developed:the hydroxysulfurization ofα,β-unsaturated amides and esters was realized without transition metal catalysts and reducing agents,with high chemical selectivity.A variety ofβ-hydroxysulfides were obtained in high yields and yields up to 96%,and the reaction was found to exhibit a broad substrate range and good functional group tolerance.