Recently, our group reported a procedure which allows preparing 1-alkynyltriazenes by a simple one-pot-reaction using nitrous oxide.[1] Subsequently, we have shown that 1-alkynyltriazenes react as activated alkynes with a reactivity profile similar to ynamides.[2] In continuation of these studies, we have used 1 alkynyltriazenes in Ru-catalyzed [2+2] cycloadditions reactions with bicyclic alkenes.  In collaboration with the group of Prof. N. Cramer, we have shown that 1-alkynyl triazenes are highly reactive substrates for enantioselective CpxRuII-catalyzed [2+2] cycloaddition reactions with bicyclic alkenes. High yields and enantioselectivities were obtained giving access to a broad range of cyclobutenyl triazenes. A salient feature of the vinyl triazenes is the behavior as divergent platform intermediates.

[1] Kiefer, G., Riedel, T., Dyson, P., Scopelliti, R., Severin, K.; Angew. Chem. 2015, 127, 306–310; Angew. Chem. Int. Ed., 2015, 54, 302–305.
[2] Perrin, F.G.; Kiefer, G.; Jeanbourquin, L.; Racine, S.; Perrotta, D.; Waser, J.; Scopelliti, R.; Severin, K. Angew. Chem. Int. Ed. 2015, 54, 13393−13396.