A Novel Trisamidophosphine Ligand and Its Group(IV) Metal Complexes

A novel trisamidophosphine ligand scaffold has been synthesized and employed to coordinate all of the group(IV) metals. The resulting complexes feature closed half-cage geometries with the phosphorus donor and all three amides binding to the metal. Out of nine complexes of the type [PN3]MX (M = Ti, Zr, Hf; X = NMe2, OTf, CH3), the zirconium derivatives have been studied by X-ray diffraction and shown to exhibit metal–phosphorus distances that are well in range of a coordinative bond. In contrast to its heavier homologues, the titanium methyl species [PN3]TiMe is prone to thermally induced ligand CH activation with concomitant loss of methane.