À. Díaz Jiménez, R. Monreal Corona, A. Saha, A. Álvarez Núñez, A. Company, T. Parella, P. J. Pérez, A. Caballero, A. Roglans, A. Poater, A. Pla-Quintana. J. Am. Chem. Soc., 2026
https://pubs.acs.org/doi/10.1021/jacs.5c19806
Herein we present compelling evidence of the intervention of electrophilic silver vinylcarbenes in the carbene-alkyne metathesis (CAM) reaction, leading to a pivotal C(sp2)-H insertion process. The delicate equilibrium between the stability and reactivity of transient species is crucial for efficient detection. Through meticulous mechanistic exploration, we unveil that the mechanism for the C(sp2)-H insertion hinges on the substitution pattern. Indeed, it departs from the previously documented stepwise mechanism (involving Wheland intermediates), and it follows a concerted route, quite uncommon for this transformation.
