Superbulky Cp ligands – CpBIG

(Bu-chains not shown)

CpBIG

Although chemistry with the superbulky ligand Ph₅Cp was initiated many years ago, it has never been fully developed for two reasons:

1. the ligands are extremely bulky. Synthesis of its simple ferrocene is not easily achieved.
2. all Ph₅Cp complexes are extremely insoluble on account of their rigidity and high symmetry.

In cooperation with the University of Cape Town (John Moss) we prepared alkylated ligands of the form (4-nBu-C₆H₄)₅Cp which we coin Cp^BIG.

The chemistry of Cp^BIG is very different from usual Cp-chemistry. The Cp^BIG ligands in (Cp^BIG)₂M metallocenes do not repel each other but instead show attraction!
This is due to an extensive network of non-classical C-H···C hydrogen bonds.

We are currently exploring this unique ligand in catalysis.

(Harder et al Angew. Chem. 2008)

Kategorie: Allgemein