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The use of volatile solvents for organic synthesis is nowadays questioned due to their negative impact on the environnement. To develop sustainable and environmentally friendly methodologies, we propose to combine two green chemistry concepts: the use of bioinspired solvents: natural deep eutectic solvents (NaDES), and mechanochemistry. Using the Suzuki‐Miyaura coupling as a model reaction, we described an efficient mechanochemical method with NaDES as a LAG (liquid‐assisted grinding) additive with short reaction times and without any ligand or additional heating. A mechanochemical extraction was also used to reduce the amounts of extraction solvents and the total time of the synthesis process. [ABSTRACT FROM AUTHOR]

Organic synthesis without an organic solvent is still the exception. In this microreview, we discuss and compare different synthetic methods that proceed in the absence of conventional organic solvents. This includes solvent‐free methods in solids (mechanochemistry and solid‐state photochemistry), and in neat liquids (thermal and photocatalytic), as well as the application of unconventional solvents, such as ionic liquids and deep‐eutectic solvents. The different approaches are briefly introduced and examples illustrate their specific advantages, followed by a critical discussion of their limitations. Some methods have the intrinsic benefits of solvent‐free operation, such as avoiding solubility problems and side‐reactions with the solvent. However, every method has specific advantages and the demand of the synthetic application is crucial for selecting the best technique. [ABSTRACT FROM AUTHOR]