Studies On Reactions Of Perfluoroalkanesulfinyl Chlorides With Terminal Alkynes And Carbonyl Compounds

As active intermediates,perfluoroalkanesulfinyl chlorides have a wide range of applications in the synthesis of fluorine-containing compounds.This dissertation focused mainly on the reactions of perfluoroalkanesulfinyl chlorides with terminal alkynes and carbonyl compounds.It consists of three parts:Part one:Using n-BuLi/ZnCl₂ system,the nucleophilic substitution reaction of perfluoroalkanesulfinyl chlorides with terminal alkynes was acheived.Alkynes and n-Bu Li were firstly stirred in n-hexane at-78℃for 1 h,Zn Cl₂was then added to generate RZn Cl species,which reacted with perfluoroalkanesulfinyl chlorides added next to give the corresponding substitution products.A series of perfluoroalkylα-alkynyl sulfoxides were synthesized in moderate to good yields by this protocol.Further investigation showed that this type of perfluoroalkylα-alkynyl sulfoxide could undergo Diels-Alder addition reaction with cyclopentadiene.Part two:The reaction of perfluoroalkanesulfinyl chlorides with carbonyl compounds was investigated.In the presence of pyridine,perfluoroalkanesulfinyl chlorides reacted smoothly with 2-methyl-1,3-dicarbonyl compounds at 80℃to give the corresponding2-methyl-2-perfluoroalkanesulfinyl-1,3-dicarbonyl products in moderate yields.Similarly,the reaction of 2-acetylcyclohexanones with perfluoroalkanesulfinyl chlorides occurred at room temperature,affording the corresponding perfluoroalkyl sulfoxide products.Furthermore,the reaction of enol silyl ethers with trifluoromethanesulfinyl chloride was achieved without any additives,and a series of trifluoromethylβ-carbonyl sulfoxides were obtained in good yields,which could be further converted to their trifluoromethylthio derivatives with phosphorus trichloride.Part three:The reaction of potassium phenylsulfonyldifluoroacetates with perfluoroalkylsulfinimides was investigated.In the absence of any bases and catalysts,phenylsulfonyldifluoroacetates underwent decomposition and coupling reaction at room temperature to give（phenylsulfonyl）difluoromethyl phenyl sulfoxide and（phenylsulfonyl）difluoromethyl phenyl sulfide products.