Reaction of [(C 6 H 6 )RuCl 2 ] 2 with 7,8-benzoquinoline and 8-hydroxyquinoline J.G. Małecki a, * , M. Jaworska b , R. Kruszynski c , J. Kłak d a Department of Inorganic and Radiation Chemistry, Institute of Chemistry, University of Silesia, 9th Szkolna Street, 40–006 Katowice, Poland b Department of Theoretical Chemistry, Institute of Chemistry, University of Silesia, 9th Szkolna Street, 40–006 Katowice, Poland c Department of X-Ray Crystallography and Crystal Chemistry, Institute of General and Ecological Chemistry, Lo ´dz ´ University of Technology, 116 _ Zeromski Street, 90–924 Lo ´ dz ´, Poland d Faculty of Chemistry, Wroclaw University, F. Joliot-Curie 14 Street, 50-383 Wroclaw, Poland Received 24 May 2005; accepted 22 June 2005 Available online 11 August 2005 Abstract The reaction of [(C 6 H 6 )RuCl 2 ] 2 with 7,8-benzoquinoline and 8-hydroxyquinoline in methanol were performed. The obtained complexes have been studied by IR, UV–VIS, 1 H and 13 C NMR spectroscopy and X-ray crystallography. In the reaction with 8-hydroxyquinoline the arene ruthenium(II) complex oxidized to Ru(III). The electronic spectra of the obtained compounds have been calculated using the TDDFT method. Magnetic properties of [Ru(C 9 H 6 NO) 3 ] Æ CH 3 OH complex suggest the antiferromagnetic coupling of the ruthenium centers in the crystal lattice. EPR spectrum of [Ru(C 9 H 6 NO) 3 ] Æ CH 3 OH compound indicates single iso- tropic line only characteristic for Ru 3+ with spin equal to 1/2. Ó 2005 Elsevier Ltd. All rights reserved. Keywords: Ruthenium arene complexes; 7,8-benzoquinoline; 8-hydroxyquinoline X-ray structure; TDDFT method 1. Introduction The g 6 -arene ruthenium complexes play a vital role in organometallic chemistry [1a,1b,1c,1d,1e]. The arene ruthenium halide compounds, obtained by Winkhaus et al. [2], are key starting materials for the formation of wide range of natural and cationic ligand derivatives [1d,3a,3b,3c,3d]. The half-sandwich arene ruthenium complexes may serve as excellent catalyst precursors for hydrogenation [3c,4a,4b,4c,4d,4e] and for ring-open- ing metathesis polymerization [4f]. Recent studies of arene ruthenium complexes have shown that they are found to inhibit cancer cell growth [5a,5b,5c,5d]. The density functional theory (DFT) has become a very popular computational method for the calculation of a number of molecular properties [6–10]. Because of its greater computational efficiency, DFT has been ap- plied extensively to inorganic and organometallic com- plexes [11–15]. The time-dependent generalization of DFT (TDDFT) offered a rigorous route to calculate the dynamic response of the charge density [16–19]. The reliability of TDDFT approach in obtaining accu- rate predictions of excitation energies and oscillator strengths is well documented. The method has been suc- cessfully used to calculate electronic spectra of transition metal complexes with variety of ligands [20–22]. 2. Experimental The starting material [(C 6 H 6 )RuCl 2 ] 2 was synthesized according to the literature procedure [23]. All other 0277-5387/$ - see front matter Ó 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.poly.2005.06.053 * Corresponding author. Tel./fax: +48 32 255911. E-mail addresses: gmalecki@us.edu.pl (J.G. Małecki), mj@tc3. ich.us.edu.pl (M. Jaworska), kruszyna@p.lodz.pl (R. Kruszynski), jmroz@wchuwr.chem.uni.wroc.pl (J. Kłak). www.elsevier.com/locate/poly Polyhedron 24 (2005) 3012–3021