Enolate Claisen Rearrangement of Esters from Furanoid and Pyranoid Glycals

Article abstract of DOI:10.1021/jo01289a012

A general method is described for the formation of furanoid and pyranoid glycals.Thus, lithium-ammonia reduction of the corresponding 1-chloro-2,3-O-isopropylidene furanoid and pyranoid carbohydrate derivatives affords the desired glycals in 87-92percent yields.Several examples that reveal the scope of this process are described .The formation of C-glycosides from the glycal esters through application of the ester enolate Claisen rearrangement is explored.The characteristics and stereochemistry of this process in both the acyclic and cyclic series of glycal derivatives are described.