An Efficient Synthesis Of2,5-diimino-furans Via Pd-catalyzed Cyclization Of Bromoacrylamides And Isocyanides

Over the last century, isocyanides have long proved themselves to be irreplaceable buildingblocks in modern organic chemistry. Accompanied with the prosperous development of thetransition metal-catalyzed reactions in the past decades, isocyanides have found a newapplication as versatile C1building blocks in transition metal catalysis. Among them, thenoble metal palladium-catalyzed reactions represent an important subclass and have attractedgreat attention. Althrough a substantial part of isocyanide chemistry, particularly in thetransitioN-metal catalyzed reaction to synthesis of heterocycles, has been explored in the last20-30years, we strongly believe this field is in its infancy and there is substantial room forfurther development.Furan derivatives, as featured moieties, occur as important scaffolds in a number ofpharmaceuticals and organic materiales. Thus, the development of novel and efficientstrategies for the assembly of furan derivatives is one of the most active areas of modernsynthetic organic chemistry. Although numerous strategies have been developed for thesynthesis of furans, there are still opportunities for the development of novel procedures forthe synthesis of new and interesting furan derivatives.On the basis of our previous study about Pd-catalyzed isocyanide involved organicsynthesis chemistry, in this context, we have studied an effient synthesis of2,5-diimine-furanderivatives from isocyanides and bromoacrylamides. In addition, we have revealed that2,5-diimine-furans could undergo hydrolysis readily to afford maleamides in almostquantitative yields which are an important class of amides and have a very wide range ofapplicaitons in the synthesis of numerous pesticides, potent pharmaceuticals as well as inelectrochemistry.