Dithioethers as ligands in pentamethylcyclopentadienylrhodium(III) and iridium(III) complexes. Crystal structures of [{(eta(5)-C5Me5)Rh}(2)(mu-Cl)(2){mu-(MeS)(2)CH2}](BF4)(2)center dot H2O and [(eta(5)-C5Me5)IrCl2{eta(1)-(PhS)(2)CH2}]

Reactions of complexes [{(eta (5)-C5Me5)MCl2}(2)] (M = Rh, Ir) with the lig and (MeS)(2)CH2 in CH2Cl2 solution led to the neutral dinuclear complexes o f the general formula [{(eta (5)-C5Me5)MCl2}(2) {mu-(MeS)(2)CH2}] [M = Rh ( 1), Ir (2)]. Compound 1 reacts in CH2Cl2 solution with silver tetrafluorobo rate in 1:2 molar ratio to yield the dinuclear cationic complex [{(eta (5)- C5Me5)Rh}(2)(mu -Cl)(2) {mu-(MeS)(2)CH2}](BF4)(2).H2O (3). Compound 2 react s with silver salts in analogous conditions to give the mononuclear cationi c complex [(eta (5)-C5Me5)IrCl{eta (2)-(MeS)(2)CH2}]BF4 (4). Reactions of t he starting complexes [{(eta5-C5Me5)MCl2}(2)] with the ligand (PhS)(2)CH2 a fforded the mononuclear complexes [(eta (5)-C5Me5)MCl2(eta (1)-(PhS)(2)CH2) ] [M = Rh (5), Ir (6)]. All the complexes have been characterised by analyt ical and spectroscopic means, and the fluxional behaviour of 4, in solution , has been studied. The crystal structures of complexes 3 and 6 have been e stablished by X-ray crystallography. Complex 3 crystallised in space group P2(1/n), a = 11.848(2), b = 12.693(2), c = 21.608(4) Angstrom, beta = 95.18 (2)degrees and Z = 4. The complex cation consists of two (eta (5)-C5Me5)Rh moieties connected by two chloride atoms and one dithioether group. The two rhodium atoms are separated by 3.6093(10) A. Complex 6 crystallised in spa ce group P2(1/c), a = 8.366(1), b = 16.011(3), c = 17.911(2) Angstrom, beta = 100.28(1)degrees and Z = 4. The iridium atom has a distorted octahedral co-ordination with a eta (5)-C5Me5 group occupying the centre of three octa hedral sites, two chloride atoms and a sulphur of a monodentate bis(phenylt hio)methane ligand. (C) 2001 Elsevier Science B.V. All rights reserved.