The oxidative conversion of the N,S-bridged complexes [{RhLL '(mu-X)}(2)] to [(RhLL ')(3)(mu-X)(2)](+) (X = mt or taz): a comparison with the oxidation of N,N-bridged analogues

The structures of [{RhLL'(mu-X)}(2)] [LL' = cod, (CO)(2), (CO)(PPh3) or {P(OPh)(3)}(2); X = mt or taz], prepared from [{RhLL'(mu-Cl)}(2)] and HX in the presence of NEt3, depend on the auxiliary ligands LL'. The head-to-tail arrangement of the two N,S-bridges is accompanied by a rhodium-eclipsed conformation for the majority but the most hindered complex, [{Rh[P(OPh)(3)](2)(mu-taz)}(2)], uniquely adopts a sulfur-eclipsed structure. The least hindered complex, [{Rh(CO)(2)(mu-mt)}(2)], shows intermolecular stacking of mt rings in the solid state. The complexes [{RhLL'(mu-X)}(2)] are chemically oxidised to trinuclear cations, [(RhLL')(3)(mu-X)(2)](+), most probably via reaction of one molecule of the dimer, in the sulfur-eclipsed form, with the fragment [RhLL'](+) formed by oxidative cleavage of a second.