Highly selective hydrogenation of α-pinene in aqueous medium using PVA-stabilized Ru nanoparticles

Polyvinyl alcohol (PVA)-stabilized ruthenium nanoparticles in water were synthesized and characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and confocal laser scanning microscope (CLSM). The Ru-PVA catalyst was highly effective for the hydrogenation of α-pinene, exhibiting higher selectivity for cis -pinane as well as high conversion. The selectivity could reach approximately 99%. The catalyst phase could be recycled at least eight times without obvious loss in the catalytic activity and selectivity. Furthermore, both the preparation of catalyst and hydrogenation of α-pinene were under mild experimental conditions. Using water as the reaction medium and PVA as the stabilizing agent made the hydrogenation process environmentally friendly. This catalytic system may also be used to convert a range of cyclenes and long chain alkenes, in particular aromatic compounds to corresponding hydrogenated products.