New Donor Functionalized Cp Ligands: Synthesis and Complexation Behaviour of Quinoxalyl and Benzothiadiazolyl Systems

Markus Enders (1) , Hubert Wadepohl , Katrin Schuhen , David Sieb

1 Anorganisch-Chemisches Institut der Universität Heidelberg

Sodium cyclopentadienide reacts as nucleophile with 4,7-dibromo-2,1,3-benzothiadiazole (BTZ) and leads to the new donor-functionalized ligand Cp^BTZ. Related quinoxalyl Cp-systems have been prepared using Pd-catalyzed coupling with zincated Cp-metal complexes. The new ligands comprise two N-donor atoms; one of them is located in a distal position relative to the metal centre so that it cannot coordinate in a chelating manner. With CpBTZ ligand derivatives several metal complexes have been synthesized. The new chromium(III) complex Cp^BTZCrCl₂(12) becomes upon activation an active catalyst for the polymerisation of ethylene. Relying on DFT-calculations and analysis of spin-density distribution combined with paramagnetic NMR-data a chelating coordination of the CpBTZ ligand is feasible in 12.

Mots clés: Physical Sciences

Markus Enders, Hubert Wadepohl, Katrin Schuhen, David Sieb. New Donor Functionalized Cp Ligands: Synthesis and Complexation Behaviour of Quinoxalyl and Benzothiadiazolyl Systems. Journal of Inorganic and General Chemistry / Zeitschrift für anorganische und allgemeine Chemie, 2009, 635 (11), pp.1560. ⟨10.1002/zaac.200900100⟩. ⟨hal-00492448⟩