Merging electrocatalytic alcohol oxidation with C-N bond formation by electrifying metal-ligand cooperative catalysts Niklas von Wolff 1 and Sitthichok Kasemthaveechok 2 1 CNRS, France and 2 Université Paris Cité The development of energy and atom efficiency processes is thought to play an important role for a sustainable chemical industry of the future. One opportunity could be the electrification of thermal processes to benefit from the inherent advantages of electrochemistry, such as safety, scalability, a cheap and traceless redox agent (electrons), and the possibility to directly control the energy input of a given reaction through the applied potential. In recent years, the construction of novel C-N bonds from simple and potentially renewable feedstock (alcohols and amines) spurred interest in the community. 1,2 This is a particular challenge due to the redox labile nature of amines, making undesired amine oxidation both thermodynamically and kinetically more facile. Here, we demonstrate that our recent efforts to electrify aromatic pincer complexes, 3 known to catalyze acceptor-less dehydrogenation reactions, can be extended to formation of C-N bonds directly from alcohols and amines. We demonstrate that such catalysts are indeed robust candidates, that allow to avoid high working potentials to access the coupling of a variety of amines substrates with benzyl alcohols. 4 By understanding possible side- reactions and the possibility to fine-tune working potentials, also simple alkyl alcohols can be coupled. With over 35 examples, TON > 90, temporal control and the possibility to easily recover unreacted alcohols, we hope that this work will spur novel developments in the field of molecular electrocatalytic alcohol oxidation. References 1. Li, J.; Zhang, Y.; Kuruvinashetti, K.; Kornienko, N. Construction of C–N Bonds from Small-Molecule Precursors through Heterogeneous Electrocatalysis. Nat Rev Chem 2022 , 6 (5), 303–319. https://doi.org/10.1038/s41570-022-00379-5. 2. Shao, J.; Meng, N.; Wang, Y.; Zhang, B.; Yang, K.; Liu, C.; Yu, Y.; Zhang, B. Scalable Electrosynthesis of Formamide through C−N Coupling at the Industrially Relevant Current Density of 120 MA Cm−2. Angewandte Chemie International Edition n/a (n/a), e202213009. https://doi.org/10.1002/anie.202213009. 3. Tocqueville, D.; Crisanti, F.; Guerrero, J.; Nubret, E.; Robert, M.; Milstein, D.; von Wolff, N. Electrification of a Milstein-Type Catalyst for Alcohol Reformation. Chem. Sci. 2022 . https://doi.org/10.1039/D2SC04533H. 4. Kasemthaveechok, S.; von Wolff, N. Merging Electrocatalytic Alcohol Oxidation with C-N Bond Formation by Electrifying Metal-Ligand Cooperative Catalysts. 2022 . https://doi.org/10.26434/chemrxiv-2022-n306b.
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