PGSE NMR studies on RAPTA derivatives:: Evidence for the formation of H-bonded dicationic species

The self-aggregation tendency of RAPTA complexes {[Ru(eta(6)-p-cymene){PTA(-R)}Cl-2]X, R = H (1BPh(4) and 1PF(6)) and Me (2BPh(4) and 2OTf), and [Ru(eta(6)-p-cymene)(PTA)(2)Cl]X (3BPh(4) and 3BF(4))} in acetone-d(6) was investigated by means of diffusion NMR spectroscopy. On increasing the concentration, the protonated species (1X) undergoes intercationic self-aggregation driven by hydrogen bonding that leads to the formation of 1(2)(2+) dications and a small amount of 1(2)X(+) ion triples.