A new tripodal, tetradentate, carbon-centered podand ligand based on HC(CH2CH2PPh2)(3) ((CP3)-C-H) has been prepared. In the presence of [RuCl2(PPh3)(3)], (CP3)-C-H dehydrogenates on heating to yield [Ru(C(CH2CH2PPh2)(2)(=CHCH2PPh2))Cl-2], where three phosphorus donors and a constrained alkene bind the metal. The metal carbon bond is then formed by reduction with hydride in the presence of an ancillary ligand, to give [Ru(C(CH2CH2PPh2)(3))LX] (L = ancillary ligand; X = H, CO, where the metal has the full CP3 donor set. The complex [Ru(CP3)(CO)H] displays moderate catalytic activity for the transfer hydrogenation of acetophenone.
Allen, O. R., Field, L. D., Magill, A. M., Vuong, K. Q., Bhadbhade, M. M., & Dalgarno, S. J. (2011). Ruthenium Complexes of CP3: A New Carbon-Centered Polydentate Podand Ligand. Organometallics, 30(23), 6433-6440. https://doi.org/10.1021/om200718j