Heterometallic Clusters with Cerium-Transition-Metal Bonding Supported by Nitrogen-Phosphorus Ligands.

Ligands are known to play a crucial role in the construction of complexes with metal-metal bonds. Compared with metal-metal bonds involving d-block transition metals, knowledge of the metal-metal bonds involving f-block rare-earth metals still lags far behind. Herein, we report a series of complexes with cerium-transition-metal bonds, which are supported by two kinds of nitrogen-phosphorus ligands N[CHCHNHPPr] () and PyNHCHPPh (). The reactions of zerovalent group 10 metal precursors, Pd(PPh) and Pt(PPh), with the cerium complex supported by generate heterometallic clusters [N{CHCHNPPr}Ce(μ-M)] (M = Pd, and M = Pt, ) featuring four Ce-M bonds; meanwhile, the bimetallic species [(PyNCHPPh)Ce-M] (M = Ni, ; M = Pd, ; and M = Pt, ) with a single Ce-M bond were isolated from the reactions of the cerium precursor supported by with Ni(COD), Pd(PPh), or Pt(PPh), respectively. These complexes represent the first example of species with an RE-M bond between Ce and group 10 metals, and and contain the largest number of RE-M donor/acceptor interactions ever to have been observed in a molecule.