Synthesis and characterization of Ru(IV) and Rh(I) complexes containing phenylimidazole ligands

Abstract

The reactions of chloro-bridged dimeric complexes [{(η3; η3-C10H16)Ru(μ-Cl)Cl}2] and [{(η4-C8H12)RhCl}2] with 1-(4-cyanophenyl)imidazole (CPI), 1-(4-nitrophenyl)imidazole (NOPI), 1-(4-formylphenyl)imidazole (FPI) and 1-(4-hydroxy-phenyl)imidazole (HPI) have been investigated. These reactions afforded complexes with the general formulations [(η3;η3-C10H 16)RuCl2(L)] (L = CPI, 1; NOPI, 2; FPI, 3; HPI, 4) and [(η4-C8H12)RhCl(L)] (L = CPI, 5; NOPI, 6; FPI, 7; HPI, 8). Resulting complexes have been characterized by analytical and spectral (IR, 1H and 13C NMR, UV-Vis) studies. Crystal structures of 2, 5 and 6 have been determined by single crystal X-ray diffraction analyses. Structural studies on the complexes 2, 5 and 6 revealed the presence of extensive inter- and intra-molecular C-H⋯X (X = O and Cl) and C-H⋯π interactions. Theoretical studies have been performed to authenticate the structures and NBO calculations to determine electronic properties of the complexes. Complexes of the general formulations [(h 3;h3-C10H16)RuCl2(L)] (L = CPI, 1; NOPI, 2; FPI, 3; HPI, 4) and [(h4-C8H 12)RhCl(L)] (L = CPI, 5; NOPI, 6; FPI, 7; HPI, 8) have been synthesized from the reactions of [{(h3;h3-C 10H16)Ru(m-Cl)Cl}2] and [{(h4-C 8H12)RhCl}2] with 1-(4-cyanophenyl)imidazole (CPI), 1-(4-nitrophenyl)imidazole (NOPI), 1-(4-formylphenyl)imidazole (FPI) and 1-(4-hydroxy-phenyl)imidazole (HPI). Resulting complexes have been fully characterized and structures of [(h3;h3-C 10H16)RuCl2(NOPI)] (2), [(h4-C 8H12)RhCl(CPI)] (5) and [(h4-C 8H12)RhCl(NOPI)] (6) determined crystallographically. Crystal structures of 2, 5 and 6 revealed the presence of extensive inter- and intra-molecular C-H⋯X (X = O and Cl) and C-H⋯p interactions. © 2010 Elsevier B.V. All rights reserved.