Structure of Cyclopentadienyl Complexes

Almeningen, A. Haaland, and S. Sandal, J. Organomet. Chem.., 149, 219 (1978) A. Haaland, VIII Polish-GDR Colloquy on Organometallic Compounds, Mausz (1977) A. Haaland, Acc. Chem. Res., 12, 415 (1979). 

Metal T Range Metal T Range Metal T Range 

The chemical shifts in cyclopentadienyl complexes (Table 9.3) occur in the 64-125 ppm range for unsubstituted C5H5 groups and up to ca 140 ppm for substituted CR5 ligands. There is a linear relationship between the and chemical shifts for the rj-CsH ligands.  

The complexation causes a considerable shift of the signal to stronger fields and the increase in the V(CH) coupling constant. The increase of screening is due to greater electron density on the carbon atoms of the ligand compared to the free ion. The 

Cyclopentadienyl complexes may be divided into the following four groups, each of which shows a characteristic IR spectrum  

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