Repurposing HER catalysis toward metal hydride-mediated electro-reductive transformations

Hydrogen evolution reaction (HER) is known as one of the most cardinal reactions in energy chemistry. In the field, tremendous efforts have been devoted to discovering highly efficient catalysts and investigating the reaction mechanism. Metal hydrides are the most critical intermediates in the HER catalysis, and they also exhibit versatile reactivity in organic transformations. Redirecting HER catalysis for metal hydride-mediated electrochemical transformations would provide effective solutions for some challenging issues in conventional organic chemistry. Although some remarkable progress has recently been achieved in the cross-subject, the synthetic chemistry community has yet to fully understand the related catalytic mechanism and catalyst design. Herein, we conclude the catalytic HER mechanism and catalyst design principles to facilitate the repurposing HER catalysis toward organic electrochemistry. Recent examples of metal hydride-mediated electro-reductive transformations have also been covered, including the reduction of unsaturated bonds and the functionalization of C–H bonds. Additionally, we discussed challenges and future developments in the field.