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Treatment of (Ar(F)')(2)Zn(OEt(2))(2) (Ar(F)' = 4-C(6)F(5)C(6)F(4)) with 2 equiv. of benzonitrile, 4-(phenyl)benzonitrile, 4(pyrrolyl)benzonitrile, pyridine, 4-(phenyl)pyridine or 4-(pyrrolyl)pyridine in dichloromethane afforded the corresponding adducts (Ar(F)')(2)ZnL(2) in near quantitative yield. The 2,2'-bipyridine adduct was prepared similarly. Multinuclear NMR spectroscopy indicated that zinc's four-coordinate character was maintained in solution. The pyridine complex crystallized from dichloromethane with a solid-state structure free of face-to-face aryl-aryl interactions. In contrast, the 4-(pyrrolyl)pyridine adduct crystallized from both dichloromethane and 1,2-difluorobenzene, with solvent of crystallization, but otherwise essentially identical supramolecular architectures assembled through aryl-aryl synthons, including a face-to-face pentafluorophenyl-pyrrole interaction

N -ferrocenyl salicylaldimine (FcPI)H, readily accessible from aminoferrocene and salicylaldehyde, reacts with dibutylmagnesium in THF to afford a red crystalline (FcPI) 2 Mg(THF) 2 ( 2 ). The reactions of the Li(FcPI) with CpTiCl 3 gave CpTiCl 2 (FcPI) · CH 2 Cl 2 ( 4 ), whereas with CpZrCl 3 · DME a mixture of three products is formed: CpZrCl(FcPI) 2 ( 5 ), CpZrCl 2 (FcPI) ( 6 ), and (FcPI) 2 ZrCl 2 · CH 2 Cl 2 ( 3 · CH 2 Cl 2 ). The crystal structures of compounds 2 – 6 are reported. Typically, the N–O chelates are oriented such that O donors are mutually trans , while N donors prefer to be trans to Cl ligands. The redox potentials of these complexes are very similar to ferrocene. On activation with methylaluminoxane, the Ti complex 4 shows moderate activity for ethylene polymerisation, while (FcPI) 2 ZrCl 2 is highly active for the oligomerisation of ethylene, to give products with average degrees of polymerisation of 12–16.

Reaction of TiCl4 with the reagents RN(SiMe3)2 in dichloromethane precipitates red to black powders (R = 1-adamantyl, phenyl, pentafluorophenyl, 3,5-bis(trifluoromethyl)phenyl), which on treatment with tetrahydrofuran gives the new THF adducts [Ti(NR)Cl(μ-Cl)(THF)2]2. The complexes are dimeric in the solid state with bridging chloride and terminal imido ligands. Activation with MAO (methylaluminoxane) gives ethene polymerisation catalysts with productivities of up to 31 kg PE [(mol complex) h bar]−1.