| Abstract |
A new class of half-sandwich (eta(6)-p-cymene) ruthenium(II) complexes supported by heterocyclic hydrazone derivatives of general formula [Ru(eta(6)-p-cymene)(Cl)(L)] where L represents N -((1H-pyrrol-2-yl)methylene) furan-2-carbohydrazide (L-1), N -((1H-pyrrol-2-yl)methylene)thiophene-2-carbohydrazide (L-2) or N -((1H-pyrrol-2-yemethylene)isonicotinohydrazide (L-3) were synthesized. Both ligand precursors and complexes were characterized by elemental and spectral analysis (IR, UV-Vis, NMR and mass spectrometry). The molecular structures of all Ru complexes [Ru(eta(6) -p-cymene)(Cl)(L)] were determined by single-crystal X-ray diffraction as threelegged piano-stool. The Ru(II) complexes were used as catalysts for the cyanosilylation of aldehydes (aliphatic, aromatic, alpha,beta-unsaturated and heterocyclic aldehydes) with trimethylsilyl cyanide (TMSCN). All reactions were performed at room temperature and catalytic conditions as solvents, catalyst and catalyst loading were experimentally optimized. Using 0.5 mol\% of Ru catalyst 3 in Et2O it was possible to prepare cyanosilylethers in good-to-excellent isolated yields. |
