doi:10.1021/acs.inorgchem.6c01357engBatuecas, MariaGarcia, BeatrizSaviozzi, ChiaraViana, Maria S.Maseras, FeliuRoyo, BeatrizMethylene-Linked Triazolylidenes as Cooperative Ligands in Manganese-Catalyzed N-AlkylationART-2026-149158We elucidate the mechanism of the manganese-catalyzed N-alkylation of aniline with benzyl alcohol mediated by a bis(1,2,3-triazolylidene) Mn(I) complex through a combination of experimental studies and density functional theory (DFT) calculations. Activation of the precatalyst by a base leads to the formation of an anionic alkoxo complex featuring a deprotonated methylene bridge, which is identified as the catalytically active species. Notably, the methylene linker exhibits previously unrecognized noninnocent behavior, undergoing reversible deprotonation and participating directly in proton-transfer steps of the catalytic cycle. Kinetic isotope effects and deuterium-labeling experiments support the involvement of both hydride transfer and alcohol-assisted proton processes in the rate-determining steps. These findings uncover a new mode of metal–ligand cooperation in triazolylidene-based manganese catalysts and provide mechanistic guidelines for the design of cooperative ligands in base-metal-borrowing hydrogen catalysis.2026http://zaguan.unizar.es/record/17104710.1021/acs.inorgchem.6c01357http://zaguan.unizar.es/record/171047oai:zaguan.unizar.es:171047info:eu-repo/grantAgreement/EC/H2020/101034288/EU/International Fellowship Programme for Talent Attraction to the Campus of International Excellence Campus Iberus/IberusExperienceThis project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 101034288-IberusExperienceInorganic Chemistry 65, 16 (2026), 9265-9273byhttps://creativecommons.org/licenses/by/4.0/deed.esinfo:eu-repo/semantics/openAccess