Insertion of a Nontrigonal Phosphorus Ligand into a Transition Metal-Hydride: Direct Access to a Metallohydrophosphorane

The synthesis and reactivity of an NPN-chelating ligand containing a nontrigonal phosphorous triamide center (L1 = P(N( o-N(2-pyridyl)C(6)H(4))(2)) is reported. Metalation of L1 with RuCl(2)(PPh(3))(3) gives RuCl(2)(PPh(3))(L1) (2). By contrast, metalation of L1 with RuHCl(CO)(PPh(3))(3) yields RuCl(CO)(PPh(3))(L1(H)) (3), a chelated 10-P-5 ruthenahydridophosphorane, via net insertion into the Ru-H bond. Hydride abstraction from 3 with Ph(3)CPF(6) gives [RuCl(CO)(PPh(3))(L1)]PF(6) (4); reaction of 4 with NaBH(4) returns 3.