Synthesis of flexible bis-intercalating ruthenium (II) complexes

We report the synthesis, resolution and characterisation of a number of novel ruthenium(II) complexes. Four mononuclear complexes, [Ru(dpq)2(3-Br-phen)]2+, [Ru(dpq)2(4-Cl-phen)]2+, [Ru(dpq)2(5-Cl-phen)]2+ and [Ru(dpq)2(phen)]2+ were synthesised (dpq = dipyrido[3,2-d:2,3-f]quinoxaline, phen = 1,10-phenanthroline, 3-Br-phen = 3-bromo-1,10-phenanthroline, 4-Cl-phen = 4-chloro-1,10-phenanthroline, 5-Cl-phen = 5-chloro-1,10-phenanthroline). These complexes were resolved using the chiral TRISPHAT anion, [tris(tetrachlorocatecholato)phosphate(V)]-. Racemic mononuclear complexes were used in the synthesis of the racemic dinuclear complexes, [{Ru(dpq)2}2-(phen-n-SOS-n-phen)]4+ (SOS = 2-mercaptoethyl ether, n = 3, 4 or 5). Resolved mononuclear complexes were used to synthesise stereoselectively the - and -enantiomers of their respective dinuclear complexes. All metal complexes were characterised by 1H NMR, ESI-MS, UV/Vis and luminescence spectroscopy. Resolved metal complexes were further characterised using CD spectroscopy and chiral 1H NMR titrations.