Phenoxy-Imine Chelates

Saito, J. Mitani, M. Mohri, J. Ishii, S. Yoshida, Y Matsugi, T. Matsui, S. et al. Highly syndiospecific living polymerization of propylene using a titanium complex having two phenoxy-imine chelate ligands. Chem. Lett. 2001, 576-577. 

Mitani, M. Furuyama, R. Mohri, J. Saito, J. Ishii, S. Terao, H. Nakano, T. Tanaka, H. Fujita, T. Syndiospecific living propylene polymerization catalyzed by titanium complexes having fluorine-containing phenoxy-imine chelate hgands. J. Am. Chem. Soc. 2003,125, 4293 305. 

Matsui, S. Mitani, M. Saito, J. Tohi, Y Makio, H. Matsukawa, N. Takagi, Y. et al. A family of zirconium complexes having two phenoxy-imine chelate ligands for olefin polymerization. J. Am. 

Kojoh, S., Matsugi, T., Saito, J. etal. (2001) New monodisperse ethylene-propylene copolymers and a block copolymer created by a titanium complex having fluorine- containing phenoxy-imine chelate ligands. Chemistry Letters, 822-823. 

Saito, J., Mitani, M., Mohri, J. et al. (2001b) Living polymerization of ethylene with a titanium complex containing two phenoxy-imine chelate hgands. Angewandte Chemie-Intemationdl Edition, 40,2918-2920. 

Chelating bis(phenoxy) imine-donor complexes, with Zr(IV)... 

Poor activity is shown by other complexes with a coordinating iV-pyridine atom. In fact, complexes 144 and 147 are not active in ethylene polymerization,1181 1184 1185 whereas complexes 145 and 146 show low to moderate activity (about 10-30gPE (mmol M) 1 h 1 bar-1) and yield PE with very low Mn (<7000).1184 However, these complexes also contain a more strained five-membered chelating ligand relative to the six-membered chelating ligands of bis(phenoxy-imine) catalysts. 

Based on the x-ray crystal structure of the [2]catenane and the DFT-calculated structure of the trefoil knot, the formation of the knotted structures resulted from a strong zinc templated chelation combined with the formation of dynamic covalent imine bonds catalyzed by Zn(II) acting as a Lewis acid and templated by strong tt-tt stacking interactions between the bipyridine of one strand and the phenoxy rings of another—an organization that predisposes the amine functions close to the formyl groups. 

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