Dibenzenechromium conformation

Dibenzenechromium, like ferrocene, exhibits eclipsed rings in its most stable conformation. The metal-ligand bonding in this compound may be interpreted using the group orbital approach applied to ferrocene earlier in Chapter 5. 

The prismatic cyclopentadienyl and benzene complexes of transition metals (see, e.g., Ref. [3-9]) are reminiscent of the polycyclic hydrocarbon prismanes. Figure 3-35 shows ferrocene, (C5Hj)2Fe, for which both the barrier to rotation and the free energy difference between the prismatic (eclipsed) and antiprismatic (staggered) conformations are very small [3-51]. Figure 3-35 presents also a prismatic model with symmetry for dibenzenechromium, (C,H,)2Cr. 

Dibenzenechromium, (i7 -C5H5)2Cr, is a sandwich compound having two parallel benzene rings in an eclipsed conformation. For this molecule,... 

A. (ti-R)2M are symmetrical sandwich type complexes represented by ferrocenes la and lb (staggered and eclipsed conformations, respectively) by dibenzenechromium (2), and by (ri -cyclopentadienyl)(Ti -benzene)manganese... 

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