Synthesis and Characterization of Some C2-Symmetric Copper(II), Ruthenium(II) and Chromium(0) Complexes with Quadridentate Ligands having 2-Quinolinyl Auxiliary Groups

Abstract

Some new octahedral transition metal carbonyl and dichloro complexes (2-7) of the tetrapodal, stereorigid amine ligands (N,N’-dibenzyl-N,N’-di(quinoline-2-methyl)-1,2-ethylenediamine (DBQED) (1a) and N,N’-dimethyl-N,N’-di(quinoline-2-methyl)-1,2-ethylene diamine (DMQED) (1b) have been prepared and characterized. The reaction of the ligands with CuCl₂.2H₂O afforded the corresponding Cu(II) dichloride complexes [(DBQED)CuCl₂] (2) and [(DMQED)CuCl₂] (3), respectively. Ru(II) complexes of the types [(DBQED)RuCl₂] (4) and [(DBQED) Ru (CO)₂Cl₂] (5) were prepared by the treatment of RuCl₃.3H₂O or Ru (CO)₂Cl₂]_n with the ligand DBQED. The chromium(0) carbonyl complexes [(DMQED )Cr(CO)₂ ] (6) and [(DBQED)Cr(CO)₄] (7) were prepared by refluxing the corresponding ligand with Cr(CO)₆ in xylene. In the complexes (2, 3, 4 and 6) the ligands act as a tetradentate chelate. While in 1 and 7 the ligand coordinates in a bidentate fashion.