Localized bond analog utility

A 16-electron, d° Cp2M(R)X species contains one low-lying metal-centered LUMO localized in the equatorial plane between the Cp ligands which is utilized for substrate coordination (Fig. 1) (11). Zr—X r-bonding (X = OR, halide, etc.) utilizes this orbital and generally results in decreased reactivity (5). The electronic structure of a Cp2Zr(R)(L) complex is similar to that of neutral analogs, but the LUMO is stabilized by the metal... 

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