Aluminabenzene–Zirconium Complexes: Intramolecular Coordination of Chloride to Aluminum

The reaction of the previously reported anionic aluminabenzene with zirconium chlorides (CpZrCl3, Cp*ZrCl3, and ZrCl4) gave novel zirconium complexes bearing aluminabenzene ligand(s). The X-ray crystallographic analysis of the resulting complexes revealed that the aluminabenzene ligand(s) coordinated to the zirconium center in an η5-fashion as a six-electron donor. Chloride ligand(s) on the zirconium center intramolecularly coordinated to the Lewis acidic aluminum atom in the aluminabenzene ring. The variable-temperature 1H NMR experiment showed a dynamic process for dissociation and recoordination of chloride to the aluminum center.