Double Strain‐Release (3+3)‐Cycloaddition: Lewis Acid Catalyzed Reaction of Bicyclobutane Carboxylates and Aziridines
Malini George, Jasper Mindner, Silas Wittmer, Daniil A. Knyazev, Daniel B. Werz
Abstract
Abstract A (3+3)‐cycloaddition to afford 2‐azabiyclo[3.1.1]heptanes was realized by reacting highly strained aryl bicyclo[1.1.0]butane (BCBs) carboxylates with tosylated aziridines. Under Sc(OTf) 3 catalysis the transformation proceeded smoothly under mild conditions to the corresponding bicyclic products bearing at the bridgeheads of the embedded four‐membered ring aryl and ester moieties, respectively. This reaction is a rare example of a cycloaddition of two highly strained ring systems under Lewis acid catalysis. Mechanistic experiments provided insights into the reaction mechanism.
Topics & Concepts
CycloadditionBicyclic moleculeCatalysisChemistryLewis acids and basesRing (chemistry)ArylMedicinal chemistryLewis acid catalysisRing strainOrganic chemistryAlkylSynthesis and Catalytic ReactionsCatalytic C–H Functionalization MethodsAsymmetric Synthesis and Catalysis