Abstract
A series of N-substituted iminopyridine ligandbased arene-Ru-II complexes with general formula [(eta(6)-arene) Ru(C5H4N-2-CH=NR) Cl](+) was synthesized and characterized by NMR spectroscopy, mass spectrometry, and singlecrystal X-ray diffraction studies. The synthesized arene-Ru-II complexes showed high activity in the regioselective Markovnikov hydration of a range of aromatic and aliphatic terminal alkynes and produced moderate to good yields of the corresponding methyl ketones. Moreover, the Ru-II catalysts studied showed good recyclability. The mechanism of the Ru-II-catalyzed hydration reaction was investigated in detail by performing mass experiments and control experiments, followed by the identification of crucial RuII-alkyne and Ru(II)vinyl organometallic species.