Advances in the electrochemical, mechanochemical, microwave-assisted and non-conventional media-based synthesis of boronic acids and esters

Boronic acids and esters are among the most versatile building blocks in modern organic synthesis. However, their preparation remains largely dominated by classical solution-phase chemistry. In recent years, unconventional catalytic strategies have emerged that exploit alternative reaction environments and activation modes, enabling access to distinct reactivity patterns. The review discusses non-conventional strategies for synthesising boronic acids and esters, focusing on electrochemical, mechanochemical, microwave-assisted and unconventional media-based approaches developed between 2020 and 2025. The analysis focuses on the impact of alternative reaction environments on (catalyst) activity, selectivity and process efficiency, as compared with classical solution-phase systems. The review identifies areas in which unconventional approaches offer genuine synthetic and operational advantages, while also outlining their current limitations and future directions.