Transition metal complexes containing functionalized organoimido and phosphaneiminato ligands

摘要

Two different types of modified imido and phosphaneiminato ligands are investigated, namely chelate ligands and redox-functionalised ligands. The first examples of di(organoimido)chromium as well as di(phosphaneiminato)titanium and niobium chelates are described. Furthermore, the first complexes containing redox-functionalised organoimido ligands are presented, together with the first structurally characterised redox-functionalised phosphaneiminato complex. Compounds of the type [(RN)(2)M(CH2Ph)(2)] (M = Cr, Mo) are used as catalysts for the (co-)polymerisation of the polar olefins methyl methacrylate, acrylonitrile and vinyl acetate. A range of X-ray crystal structure determinations provide clear evidence for the quantum-chemical result that, similar to organoimido complexes, the potential energy well for the angle at the nitrogen atom is very shallow for phosphaneiminato complexes. [References: 74]