Synthesis, reactivity and catalytic properties of the allenylidene [Ru(CCCPh2)Cp(PTA)(PPh3)](CF3SO3) (PTA = 1,3,5-triaza-7-phosphaadamantane)

Synthesis of water-soluble ruthenium clusters by reaction with PTA (1,3,5-triaza-7-phosphaadamantane)

“…gives a sharp singlet at δ = -45.2 ppm, which shows that each ruthenium atom bears a phosphine and that these are all equivalent. In general these results are a lot clearer than for the [Ru 5 C(CO) 15 ] equivalents thanks to the more symmetrical structure of [Ru 6 C(CO) 17 ].…”

“…[Ru 6 C(CO) 17 ] derivatives, one can see that the first ones are more soluble, which we think is inherent to the mother cluster, already more soluble in organic solvents than [Ru 6 C(CO) 17 ].…”

“…The methodology is straightforward, starting from CO-only clusters, and introducing the PTA ligand in the coordination sphere by ligand exchange. The various stoichiometries of Ru atoms:PTA ligands will be explored for the [Ru 3 (CO) 12 ], [Ru 5 C(CO) 15 ] and [Ru 6 C(CO) 17 ] compounds, and their water-solubility assessed. All new species will be purified and fully characterized.…”

“…[Ru 3 (CO) 12 ], [Ru 5 C(CO)15 ] and [Ru 6 C(CO)17 ] were reacted with PTA to afford new clusters 4-5 and 9-20. It is proven that the PTA ligand adds itself to ruthenium clusters very easily thanks to its low Tolman angle, leading to a mix of products that has to be separated.…”

“…It is proven that the PTA ligand adds itself to ruthenium clusters very easily thanks to its low Tolman angle, leading to a mix of products that has to be separated. Up to one PTA ligand per ruthenium atom can be added in the coordination sphere of the carbonyl clusters, giving three different products from [Ru 3 (CO)12 ], five from [Ru 5 C(CO) 15 ] (a sixth product is however proposed) and six from [Ru 6 C(CO)17 ].It can be seen that for the [Ru 3 (CO)12 ] derivatives, the water-solubility property is reached when there is saturation, i.e. one phosphine per ruthenium atom.…”