Construction of a stable N-heterocyclic phosphenium cation with an electron-rich framework and its complexation to rhodium

Article abstract of DOI:10.1021/om060466b

The synthesis and characterization of a new N-heterocyclic phosphenium cation captured in a six-membered, electron-rich framework is presented. The cation reacts quantitatively with 1 equiv of Wilkinson's catalyst, Rh(PPh ₃)₃Cl, to form a cationic rhodium - phosphenium complex, the first to be characterized in the solid state. Computational and X-ray diffraction studies support the existence of a strong dπ - pπ bond between rhodium and phosphorus.