Recent progress in selective functionalization of diols via organocatalysis

Polyols bearing multiple hydroxyl groups present persistent challenges for site-selective functionalization due to their inherent reactivity similarity. As minimal polyol systems, diols offer a practical and conceptually rich platform for developing regioselective catalytic strategies. This review highlights recent progress in organocatalyzed diol functionalization, with a survey of organocatalysts incorporating boron, nitrogen, and phosphorus-based motifs, as well as emerging photoredox methodologies. These systems enable selective transformation under mild conditions, avoiding stoichiometric activation and minimizing reaction complexity. Steric and electronic effects, along with noncovalent interactions, are examined in detail to rationalize the observed selectivity and guide the rational design of catalysts. This review offers a conceptual foundation for advancing sustainable, selective methods in diol derivatization.