Titanium complexes neutral donors

The importance of neutral donors in the ligand framework of living olefin polymerization catalysts was also demonstrated recently by Sundararajan and coworkers. In 2002, the authors reported titanium dichloride complexes of tridentate aminodioi ligands me- and meso-45, Figure 13) treated with MAO furnished PHs possessing relatively narrow Figure 14 Titanium precataiysts for styrene poiymerization. 

Neutral compounds such as boron trifluoride and aluminum trichloride form Lewis acid-base complexes by accepting an electron pair from the donor molecule. The same functional groups that act as electron pair donors to metal cations can form complexes with boron trifluoride, aluminum trichloride, titanium tetrachloride, and related compounds. In this case the complex is formed between two neutral species, it too is neutral, but there is a formal positive charge on the donor atom and a formal negative charge on the acceptor atom. 

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