Advances and Challenges for the Synthesis of Organoboron Compounds in Water

Organoboron chemistry plays a central role in modern organic synthesis with direct impact in academy and pharmaceutical industry, where the Suzuki-Miyaura stands out as the most popular reaction. Considering the increasing demand for environmentally more sustainable practices, the Suzuki-Miyaura reaction has evolved and considerable effort has been devoted to transitioning this reaction from traditional organic solvents to water and reducing the amount of palladium used. On the other hand, little attention has been paid to the development of more sustainable methodologies for the synthesis of the requisite organoboron starting materials. This review highlights advances in the development of organoboron chemistry in water, focusing on three key areas: (i) borylation of aryldiazonium salts, (ii) Miyaura borylation, and (iii) emerging strategies for hydroboration of alkynes. These approaches demonstrate that water can serve not only as a benign solvent but also as a unique reaction medium that enables new reactivity and improved sustainability.