Azaruthena(II)‐bicyclo[3.2.0]heptadiene: Key Intermediate for Ruthenaelectro(II/III/I)‐catalyzed Alkyne Annulations
Long Yang, Ralf Steinbock, Alexej Scheremetjew, Rositha Kuniyil, Lars H. Finger, Antonis M. Messinis, Lutz Ackermann
Abstract
A ruthenium-catalyzed electrochemical dehydrogenative annulation reaction of imidazoles with alkynes has been established, enabling the preparation of various bridgehead N-fused [5,6]-bicyclic heteroarenes through regioselective electrochemical C-H/N-H annulation without chemical metal oxidants. Novel azaruthenabicyclo[3.2.0]heptadienes were fully characterized and identified as key intermediates. Mechanistic studies are suggestive of an oxidatively induced reductive elimination pathway within a ruthenium(II/III) regime.
Topics & Concepts
AnnulationBicyclic moleculeAlkyneRegioselectivityRutheniumCatalysisChemistryMedicinal chemistryElectrochemistryReductive eliminationCombinatorial chemistryStereochemistryOrganic chemistryElectrodePhysical chemistryCatalytic C–H Functionalization MethodsRadical Photochemical ReactionsAsymmetric Hydrogenation and Catalysis