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

Abstract

The synthesis and reactivity of an NPN-chelating ligand containing a nontrigonal phosphorous triamide center (L1 = P(N(o-N(2-pyridyl)C₆H₄)₂) is reported. Metalation of L1 with RuCl2(PPh₃)₃ gives RuCl2(PPh₃)(L1) (2). By contrast, metalation of L1 with RuHCl(CO)(PPh₃)₃ yields RuCl(CO)(PPh₃)(L1[superscript H]) (3), a chelated 10-P-5 ruthenahydridophosphorane, via net insertion into the Ru–H bond. Hydride abstraction from 3 with Ph₃CPF₆ gives [RuCl(CO)(PPh₃)(L1)]PF₆ (4); reaction of 4 with NaBH₄ returns 3.