Green chemistry and flow chemistry are ideal partners for accessing novel chemical spaces and define highly efficient synthetic tools.

γ-Valerolactone (GVL) is an excellent reaction medium, derived from biomasses, which can replace classic dipolar aprotic media such as DMF or NMP.

γ-Valerolactone (GVL) can be used as an efficient and practical alternative to the banned and commonly used dipolar aprotic solvents.

γ-Valerolactone (GVL) can be a valid biobased replacement for toxic dipolar aprotic solvents especially in widely used cross-coupling reactions. In this contribution, we have proved that GVL can be a useful medium for the Hiyama reaction, and we developed a practical and efficient protocol for the Hiyama coupling using a nonexpensive and commercially available heterogeneous palladium catalyst without the use of any ligand or additive. Desired cross-coupling products 3a−m have been obtained in good to excellent yields (74−94%).

A highly sustainable and waste-minimized protocol for Heck coupling has been defined. Optimal conditions have been defined by exploiting a heterogeneous catalyst based on supported ionic liquid-like phases featuring high Pd loading (10 wt %) and by optimizing its efficiency in a recoverable green reaction medium (acetonitrile/water azeotrope). Pure products 4a–l and 6a–h have been isolated chromatography-free in high yields (74–99%) and with extremely low environmental factor (E-factor) values (2.3–5.0). With the application of flow technology, the selected heterogeneous base and Pd catalyst have been fully recovered and reused, and minimum palladium leaching allowed for isolation of the final products with low residual palladium content (<5 ppm) without any purification step

In this contribution, we present a chemically efficient and sustainable protocol for the palladium-catalyzed copper-free Sonogashira cross-coupling reaction, based on the use of a heterogeneous catalytic system. This consists in the combination of a palladium catalyst on highly cross-linked thiazolidine network on silica and a polystyrene-supported base. The solid catalyst/base system acts as a palladium scavenger avoiding leaching of the metal and consequent product contamination. The reaction can be conducted in safe and easily recoverable acetonitrile/water azeotrope as reaction medium. This proved to be an efficient greener alternative to the classic toxic aprotic media commonly used in cross-coupling reaction, such as DMF and NMP. Acetonitrile/water azeotrope could be easily recovered and reused allowing the minimization of waste production. Our approach, based on the use of both a supported base and a supported catalyst, has proven to be efficient for the waste reduction, as proved by the low E-factor values achieved

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