Preparation of the Ru-3(CO)(8)-pyridine-alcohol cluster and its use for the selective catalytic transformation of primary to secondary amines

The synthesis of pyridine alcohol based ruthenium carbonyl clusters Ru-3(hep)(2)(CO)(8) (1), Ru-3(hpp)(2)(CO)(8) (2), and Ru-3(bhmp-H)(2)(CO)(8) (3) {hep-H = 2-(2-hydroxyethyl)pyridine, hpp-H = 2-(3-hydroxypropyl)pyridine and bhmp-H-2 = 2,6-bis(hydroxymethyl)pyridine} has been carried out by the reaction of the corresponding pyridine-alcohol ligands with Ru-3(CO)(12). Clusters 1-3 have been characterized using elemental analysis, NMR, FT-IR, mass spectrometry and single-crystal X-ray structures. The clusters were explored for the selective catalytic transformation of primary amines into secondary amines using alcohols as the mono-alkylating agents via hydrogen transfer reactions. All three display efficient catalytic activity with 1 being the most effective.