Bimetallic ruthenium-tin chemistry: Synthesis and molecular structure of arene ruthenium complexes containing trichlorostannyl ligands

A series of neutral, anionic and cationic arene ruthenium complexes containing the trichlorostannyl ligand have been synthesised from SnCl2 and the corresponding arene ruthenium dichloride dimers [(eta(6)-arene)Ru(mu(2)-Cl)Cl](2) (arene = C6H6, (PrC6H4Me)-C-i). While the reaction with triphenylphosphine and stannous chloride only gives the neutral mono(trichlorostannyl) complexes [(eta(6)-C6H6)Ru(PPh3)(SnCl3)Cl] (1) and [(eta(6)-(PrC6H4Me)-C-i)Ru(PPh3)(SnCl3)Cl] (2), the neutral di(trichlorostannyl) complex [(eta(6)-(PrC6H4Me)-C-i) Ru(NCPh)(SnCl3)(2)] (3) could be obtained for the para-cymene derivative with benzonitrile as additional ligand. By contrast, the analogous reaction with the benzene derivative leads to a salt composed of the cationic mono(trichlorostannyl) complex [(eta(6)-C6H6)Ru(NCPh)(2)(SnCl3)](+) (5) and of the anionic tris(trichlorostannyl) complex [(eta(6)-C6H6)Ru(SnCl3)(3)](+) (6). On the other hand, [(eta(6)-(PrC6H4Me)-C-i)Ru(mu(2)-Cl) Cl](2) reacts with SnCl2 and hexamethylenetetramine hydrochloride or 18-crown-6 to give the anionic di(trichlorostannyl) complex [(eta(6)-(PrC6H4Me)-C-i)Ru(SnCl3)(2)Cl] (4), isolated as the hexamethylenetetrammonium salt or the chloro-tin 18-crown-6 salt. The single-crystal X-ray structure analyses of 1, 2, [(CH2)(6)N4H][4], [(18-crown-6)SnCl][4] and [5][6] reveal for all complexes a pseudo-tetrahedral pianostool geometry with ruthenium-tin bonds ranging from 2.56 (anionic complexes) to 2.60 angstrom (cationic complex). (C) 2009 Elsevier B.V. All rights reserved.