Facile, Thermoreversible Cycloaddition of Small Molecules to a Ruthenium(II) Arene β-Diketiminate

Formation of a vacant coordination site on a Ru center permits an unusual binding of small molecules such as ethylene, acetylene, and dihydrogen, resulting in the transformation of the chelating β-diketiminate ligand to a β-diimine. These representative species are observed during the catalytic hydrogenation of styrene.