A method for the electrochemical synthesis of sulfinic esters by aerobicoxidative coupling of thiophenols and alcohols has been developed. Using electrons as the redox reagent and O2 in air as the oxygen source, the reactions proceeded smoothly at room temperature, even for a gram-scale preparation. No use of catalyst, clean redox reagent, green and abundant oxygen source, and mild reaction conditions
Efficient electrosynthesis of sulfinic esters via oxidative cross‐coupling between alcohols and thiophenols
作者:Fengping Gong、Fangling Lu、Lin Zuo、Qi Wang、Ru Li、Jiaxin Hu、Zhen Li、Abdelilah Takfaoui、Aiwen Lei
DOI:10.1002/jccs.201900246
日期:2020.2
A new protocol for SO bond formation was developed by electrochemical oxidative cross‐coupling between alcohols and thiophenols. With this strategy, a series of valuable sulfinicester derivatives were synthesized up to 96% yield from basic starting materials. A preliminary mechanistic investigation reveals that this reaction involves oxygen reduction reaction (ORR).
One-pot syntheses of sulfinates, sulfinamides, and thiosulfinates by O-, N-, and S-sulfinylations of alcohols, amines, and thiols with p-toluenesulfinic acid in the presence of various activating reagents, phenyl phosphorodichloridate (1), diphenyl phosphoro-chloridate (2), triphenylphosphine N-chlorosuccinimide (NCS) (3), and 3-(phthalimidoxy)-1, 2-benzoisothiazole 1, 1-dioxide (4), were investigated. All of these reagents were reasonably effective for O-and S-sulfinylation, but ineffective for N-sulfinylation. Among them, the reagents 1 and 2 were slightly more efficient than the others.
A convenient and efficient method for the synthesis of various structurally functionalized sulfinates shows good substrate generality of alcohols and sodium sulfinates.
Reaction of alcohols with sodium arenesulfinates could afford either sulfones or sulfinates, and O‐attack of sulfinate anions onto in situ generated carbocation intermediates from alcohols was the previous proposed mechanism in many syntheses of sulfinates. This concept, which is often used consciously or unconsciously, was revised herein by using isotopic labeling experiments and development of an