Half-Sandwich Ruthenium Complexes with Hydrazone Ligands: Preparation, Structure, and Catalytic Activity in Cyanosilylether Synthesis under an Air Atmosphere.

Abstract

A new class of N,O-coordinate half-sandwich ruthenium complexes supported by hydrazone ligands with a general formula of [Ru(η6-p-cymene)Cl(L)] have been obtained in moderate to excellent yields conveniently. These air- and moisture-stable ruthenium complexes exhibited excellent catalytic activity in cyanosilylether synthesis under mild reaction conditions. Under the catalysis of ruthenium, various cyanosilylethers with different substituents were obtained through a one-pot reaction of trimethylsilyl cyanide with carbonyl substrates, with good to excellent yields. Excellent catalytic efficiency, a wide substrate range, and mild reaction conditions made this type of ruthenium catalyst have potential for industrial application. All of the half-sandwich ruthenium complexes have been well described by infrared, nuclear magnetic resonance, and EA analysis. Molecular structures of ruthenium complexes 1 and 4 were confirmed by single-crystal X-ray analysis.