Binuclear ruthenium η6-arene complexes with tetradentate N,S-ligands containing the ortho-aminothiophenol motifElectronic supplementary information (ESI) available. CCDC 967363. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c3dt53075b

A series of cationic binuclear (η 6 -cymene-Ru) 2 complexes with N 2 S 2 -ligands were synthesized in 64% to 85% yield by reaction of [Ru(η 6 -cymene)Cl 2 ] 2 with bis-S , S ′-( ortho -aminothiophenol)-xylenes as BF 4 − and PF 6 − salts. The compounds were studied using NMR, HRMS, UV-vis and IR spectroscopy, EA and inductively coupled plasma (ICP) MS. It was determined that the hinged binuclear Ru complexes were anti and syn diastereomers obtained in 2 : 1 ratio for ortho - and meta -xylylene bridged ligands and in a 1 : 1 ratio for the para -xylylene bridged ligand. An anion effect was found for the presence of NaBF 4 with the meta -xylylene bridged system yielding the targeted binuclear Ru complex and a mononuclear Ru complex. This mononuclear S , S ′-coordinated η 6 -cymene Ru chloride structure lacked amine-metal coordination and was obtained in a 1 : 3 ratio of anti : syn diastereomers which were insoluble in CH 2 Cl 2 and soluble in DMSO and DMF. X-ray crystallographic analysis was obtained for the N 2 S 2 ligand, 1,2- bis {(2-aminophenyl)thiomethyl}benzene, showing a C S symmetry with amine groups facing outwards with a tilt of 28.95° from the ortho -aminothiophenol pendant ring. The interatomic sulfur-sulfur distance (S-S′) is 4.6405 Å within the crystal structure while accommodating a potential metal bite angle from 1.0 Å to 5.9 Å when allowing rotation of the methylene phenyl bond. Xylylene bridged N 2 S 2 -ligands are an excellent ligand platform for tunable metal-metal distances in hinged binuclear p -cymene ruthenium complexes.