Cp2M + complexes, applications

Application of Density Functional Theory in Organometallic Complexes A Case Study of Cp2M Fragment (M =Ti, Zr) in C—C Coupling and Decoupling Reactions... 

Titanium and zirconium chemistry is conveniently divided between simple complexes and those based on the metallocene imit Cp2M (Cp = CsHs = cyclopentadienyl). Most simple complexes are oligomeric, insoluble, and difficult to characterise, although alkyl titanium complexes such as X3TiR have found some use as non-basic Grignard equivalents. The dicyclopenta-dienyl metal moiety, Cp2M, renders complexes monomeric, soluble, and easily characterised by NMR spectroscopy, and thus many applications based on these systems have been devised. The most stable electronic configuration of titanocene and zirconocene complexes has only 16 electrons in the valence shell, not the 18 electrons common in most of the rest of the transition metal series. The empty orbital this leaves on the metal is crucial for reactivity. 

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