Reassembly of Unsaturated C–C Bonds by a Cutting/Insertion Cascade

Abstract The reassembly of unsaturated C–C bonds has attracted widespread attention from synthetic chemists due to its advantages of unique reactivity, easy handling, and high atom and step economies. We recently explored a cutting/insertion cascade as a means of introducing a new C1 source and constructing functionalized 1,4-keto aldehyde and 2H-furan derivatives through cyclopropanation of enamines with various carbene precursors and subsequent ring-opening reactions in situ. Aminocyclopropanes are believed to be involved as key intermediates in these transformations. This Synpacts article outlines our recent contributions to this increasingly important research area. 1 Introduction 2 Cleavage of Enamine C=C Double Bonds and Hydrolysis to 1,4-Keto Aldehydes 3 Cleavage of Enamine C=C Double Bonds and Cyclization to 2H-Furans 4 Cleavage of Ynone/Ynoate C≡C Triple Bonds 5 Conclusion