Open metallocenes ligand complexes

In addition to the mixed Cp/carborane complexes, there has been one report on the lanthanacarboranes with the open pentadienyl ligand, R7C5 (R = H or an alkyl derivative). This is an alternate 6-7T electron donor that has led to the syntheses of number of so-called open metallocenes where the pentadienyl group replaces one or more Cp ligands. This lanthanacarborane report covered the syntheses and structural determinations of two open... 

Complexes containing an open chain are also metallocenes analogs. For instance, pentadienyl anions see Pentadienyl Ligand) form open metallocenes with transition metals as efficiently as do cyclopentadienyls. Half-open metallocenes can be obtained in a similar way starting from CpZrCl2Br (Scheme 17). ... 

C. Open Metallocene Complexes with Halide and Related Ligands. 149... 

Section 14 14 Transition metal complexes that contain one or more organic ligands offer a rich variety of structural types and reactivity Organic ligands can be bonded to a metal by a ct bond or through its it system Metallocenes are transition metal complexes m which one or more of the ligands is a cyclopentadienyl ring Ferrocene was the first metallocene synthesized Its electrostatic potential map opens this chapter... 

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