Selective hydrogenation of α, β-unsaturated aldehydes/ketones via photocatalytic and electrocatalytic techniques: A review

The selective hydrogenation of α, β-unsaturated aldehydes/ketones, while preserving other functional groups within the molecule, is of paramount importance in synthetic chemistry for the precise modulation of product structures and properties. This is particularly crucial in the synthesis of complex and high-value organic molecules. As sustainability concerns intensify, the development of catalytic technologies that adhere to green chemistry principles has become an urgent imperative. These advancements not only address the rising demand for chemicals but also respond to the global call to mitigate unsustainable practices. This review focuses on the selective hydrogenation of α, β-unsaturated aldehydes/ketones, highlighting significant progress and breakthroughs in photocatalysis and electrocatalysis within the non-traditional thermal catalysis framework over the past decade. It provides an in-depth analysis of the characteristics and design principles of catalysts, catalytic systems, performance metrics, and the mechanistic pathways involved. Moreover, this review examines the factors influencing the selective hydrogenation of CC/CO bonds, pinpointing potential focal points for the development of green and sustainable hydrogenation systems for these compounds. Through elucidating these advancements, the review aims to offer valuable insights for further innovations in green and sustainable synthetic chemistry.