Ruthenium-Catalyzed Electrochemical Ketone Hydrogenation to Secondary Alcohols with High Activity and Selectivity Under Ambient Conditions.

Secondary alcohols are indispensable building blocks in the production of fine chemicals, pharmaceuticals, and polymers, yet their conventional synthesis routes are energy and resource intensive. Electrochemical ketone hydrogenation under ambient conditions offers an attractive approach to synthesize secondary alcohols, but this process is often hindered by base-catalyzed self-condensation, hydrogenolysis, and competitive hydrogen evolution reaction (HER). Herein, we demonstrate that Ru nanoparticles supported on commercial carbon black (RuNP/C) can enable efficient, selective, and stable electrochemical hydrogenation of a wide range of structurally diverse ketones to produce corresponding secondary alcohols under ambient conditions. Mechanistic investigations reveal that RuNP/C can simultaneously promote generation of reactive hydrogen species and adsorption of ketone molecules, facilitating rapid transfer of reactive hydrogen species to adsorbed ketone molecules, thereby enabling efficient secondary alcohols formation and suppressing HER. This work opens a green and sustainable pathway for ketone upgrading.