γ-Valerolactone as a Renewable Dipolar Aprotic Solvent Deriving from Biomass Degradation for the Hiyama Reaction

摘要

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%).