Synthetic, spectral and structural studies of some homo and hetero binuclear arene ruthenium (II) polypyridyl complexes

Homo-hetero binuclear cationic complexes with the formulation [(eta(6)-arene)RuCl(mu-dpp)(L)](+) (eta(6)-arene = benzene; L = PdCl2 (1a); PtCl2 (1b), and eta(6)-arene = p-cymene; L = PdCl2 (2a); PtCl2 (2b)), [(eta(6)-arene)RuCl(mu-dpp)(L)](2+)(eta(6)-arene = p-cymene; L = [(eta(6)-C6H6)RuCl] (2c), and [(eta(6)-C10H14)RuCl] (2d)) were prepared. Molecular structure of the representative homo binuclear complex [{(eta(6)-C10H14)RuCl}(mu-dpp) {(eta(6)-C10H14)RuCl}](PF6)(2) (2d) was determined crystallographically. Weak interaction studies on the complex 2d revealed stabilisation of the crystal packing by weak inter and intra molecular C-H... X (X = F, Cl, pi) and pi-pi interactions. The C-H... F interactions lead to parallel helical chains and encapsulation of counter anion in self-assembled cavity arising from C-H-... pi and pi-pi weak interactions. (c) 2005 Elsevier B.V. All rights reserved.