Investigation On Palladium-Catalyzed Sulfonylation Of Propiolates

With the development of the concept of green chemistry and atomic economy,developing an efficient,environmentally friendly,easy to operate and mild reaction conditions to construct a specific molecular framework unit has attracted the attention of many organic chemists.Compared with alkynes,the carbon-carbon triple bonds of propiolates due to the presence of ester groups.As positioning groups,ester groups can make influence on the stereoselectivity of the reaction.Therefore,as an important raw material in the field of organic synthesis,synthetic methods of propiolates have been fully developed.As important structural motifs of many biologically active compounds or medicines and versatile building blocks for various organic transformations,Vinyl sulfone derivatives have been widely used in medicinal chemistry and material science.The synthesis and conversion of vinyl sulfone derivatives have always been the focus of chemists' research.The cross-coupling of sulfonyl resource with olefins and their derivatives,terminal alkyne or aryl propionic acid is an important strategy for the synthesis of vinyl sulfones derivatives.Most vinyl sulfones synthesized with the known methods only contains di-substituted vinyl structures.however,there are still few reports on the use of internal alkynes to construct multi-substituted vinyl sulfones with large steric substituents.Therefore,we believe that exploring more selective methods for prepare multi-substituted vinyl sulfones containing large steric substituents still has great potential.we have developed a palladium-catalyzed sulfonation of propiolates with sulfonyl hydrazides to prepare vinyl sulfone derivatives.This method allows to construct multisubstituted vinyl sulfones containing large steric substituents with high regio-and stereoselectivity,has the advantages of mild conditions,simple operation,harmless by-products,etc.