Application Of Sulfohydrazide In Alkenes/alkynes Sulfonation And Oximation And Its Application As Arylating Reagent

Oxime and sulfone compounds have a number of biological activities and are widely used in disinfectant,insect repellent,antidote,sensor,and natural products.In addition,oxime can not only be converted into amide,nitrile,oxime ether and other functional groups,but also be a common synthon in organic chemistry.The preparation of oxime is usually realized by the condensation of hydroxylamine and carbonyl compounds,which requires higher reaction temperature and longer reaction time.The preparation method is complicated,and the safety of raw material hydroxylamine is restricted by other factors such as large-scale use.In addition,aryl ketone is an important fine chemical raw material,widely used in medicine,photosensitizer synthesis and so on.From the classic Meerwein arylation reagents--aryl diazonium compounds,Chemists have developed aryl halides,aryl boric acid,Grigard reagents,aryl aldehydes and many other new aryl reagents to synthesize aryl ketones,constantly enriching the synthesis methodology.Based on the above facts,we investigated the sulfonation and oximization of alkenes or alkynes under different conditions and the coupling reaction of sulfohydrazide as the source of aryl reagents by using the characteristics of sulfohydrazide molecules and combining the interesting of our research group in aqueous organic reactions.These content be summarized into the following three parts:Section 1:Sulfohydrazide and tert-butyl nitrite(TBN)can realize alkene sulfonation and oximization cascade reaction in alkali-regulated aqueous phaseWe successfully develop asulfonation and oximation cascadereaction of alkenes through the adjust of alkali in water at 100?.The mechanism studies showed the reaction experienced a radical way.Compared with the traditional method,this method that was constructed by our group does not need metal catalyst,and the reaction can be carried out in pure water solvent without the protection of inert gas.The substrates have a wider range which both aromatic and aliphatic substrates and heterocyclic substrates can be applied to the system.This provides a simple and direct method for the synthesis of alpha-sulfonylethanone oximes.Section 2:Sulfohydrazide and TBN realize the sulfonation and oximization cascade reaction of alkynes in alkali-regulated ethanol-water systemIn environmentally benign ethanol-water systems,alkynes were used as the substitution of alkenes with the help of sulfohydrazide,and subsequently sulfonation and oximization cascade reaction was carried out to generate alpha-sulfonylketoximes.In the mechanism studies,it was found that sulfohydrazide was first oxidized by TBN to sulfonyl hydrazine free radical,and then sulfonyl free radical and diimide were released.Subsequently,the diimide reduces alkynes to alkenes.The resulting alkene reacts with the sulfonyl radical formed in the above step to produce the target products.Due to the demand of alkynes for reducing agents,the diimide was released from sulfohydrazide.The reaction can be carried out in alcohol-water system.In addition,the implementation of the g-scale reaction and the effective transformation of functional groups make the reaction conform to the characteristics of green reaction and have potential industrial application prospects.Section 3:Palladium catalyzed the synthesis of aryl ketones with sulfonyl hydrazide and aldehydesBy using palladium as catalyst for desulfurization,sulfonyl hydrazine was used as aryl reagent to generate aryl ketones by coupling with aldehydes in the aqueous phase system.The ideal reaction conditions was found through optimized the reaction factors such as the solvent,ligand and other parameters.As the substrate expands,it is found that the electron-rich substrate can be better applied to the system.In a word,these methodologies are mainly oriented to the green chemistry of aqueous phase.The reaction mechanism was investigated in detail through modern analytical means such as UHPLC,GC-MS,UHPLC-QTOF/MS,etc.In particular,the different transformation of sulfonylhydrazine and TBN in the alkene or alkyne reaction system enriched our understanding about sulfonation and oximization.This study provides a new idea for the synthesis methodology of aqueous green reaction and sulfonyl hydrazine.