Phosphinidene complexes of scandium: powerful PAr group-transfer vehicles to organic and inorganic substrates.

The first phosphinidene complexes of scandium are reported in this contribution. When complex (PNP)Sc(CH(3))Br (1) is treated with 1 equiv of LiPH[Trip] (Trip = 2,4,6-(i)Pr(3)C(6)H(2)), the dinuclear scandium phosphinidene complex (PNP)Sc(mu(2)-P[Trip]) (2) is obtained. However, treating 1 with a bulkier primary phosphide produces the mononuclear scandium ate complex [(PNP)Sc(mu(2)-P[DMP])(mu(2)-Br)Li] (3) (DMP = 2,6-Mes(2)C(6)H(3)). The Li cation in 3 can be partially encapsulated with DME to furnish a phosphinidene salt derivative, (PNP)Sc(mu(2)-P[DMP])(mu(2)-Br)Li(DME)] (4). We also demonstrate that complex 3 can readily deliver the phosphinidene ligand to organic substrates such as OCPh(2) and Cl(2)PMes* as well as inorganic fragments such as Cp(2)ZrCl(2), Cp*(2)TiCl(2), and Cp(2)TiCl(2) in the presence of P(CH(3))(3). Complexes 2-4 have been fully characterized, including single crystal X-ray diffraction and DFT studies.