Acid‐ and Base‐Catalyzed Hydrolytic Hydrogen Evolution from Diboronic Acid

Abstract

AbstractThe efficient production of H2 from hydrogen‐rich sources, particularly from water, is a crucial task and a great challenge, both as a sustainable energy source and on the laboratory scale for hydrogenation reactions. Herein, a facile and effective synthesis of H2 and D2 from only acid‐ or base‐catalyzed metal‐free hydrolysis of B2(OH)4, a current borylation reagent, has been developed without any transition metal or ligand. Acid‐catalyzed H2 evolution was completed in 4 min, whereas the base‐catalyzed process needed 6 min. The large kinetic isotopic effects for this reaction with D2O, deuteration experiments and mechanistic studies have confirmed that both H atoms of H2 originate from water using either of these reactions. This new, metal‐free catalytic system holds several advantages, such as high efficiency, simplicity of operation, sustainability, economy, and potential further use.