Palladium‐Catalyzed Ring‐Opening Addition of Activated Vinyl Cyclopropanes with N‐Tosylhydrazones.

Ring‐opening addition reaction of activated vinyl cyclopropanes with N‐tosylhydrazones in the presence of palladium(0) and triphenylphosphine affords N‐tosylhydrazone butenylmalonate compounds. Aromatic aldehyde‐derived N‐tosylhydrazones produced terminal and internal N‐allylated products, in which the terminal products are the main. While ketone‐derived tosylhydrazones produced only terminal addition products. The transformation relationship of the terminal and internal N‐allylated products in the reaction was also observed. A reasonable mechanism is proposed based on preliminary experimental results. [ABSTRACT FROM AUTHOR]