Aluminum Halides and Phosphaethynolates with Acenaphthene-1,2-Diimine Ligands

The reduction of ArBIG-bian (ArBIG-bian is 1,2-bis[(2,6-dibenzhydryl-4-methylphenyl)imino]acenaphthene) with an excess of metallic aluminum in the presence of AlCl3 in tetrahydrofuran leads to the formation of aluminum complex [(ArBIG-bian)AlCl(THF)] (1). The reaction of compound 1 with sodium phosphaethynolate yields the diamagnetic product of aluminum with phosphaethynolate ligand [(ArBIG-bian)Al(OCP)(DME)] (2a). Aluminum complex [(dpp-bian)AlCl(i-Pr2ImMe)] (3) (dpp-bian is 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) was obtained by the reaction of the disodium salt of dpp-bian with AlCl3 and 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene (i-Pr2ImMe), and compound [(dpp-bian)AlI(i-Pr2ImMe)] (4) was synthesized by replacing the diethyl ether molecule in the complex [(dpp-bian)AlI(Et2O)] with the carbene ligand i-Pr2ImMe. The metathesis reaction of iodide 4 with sodium phosphaethynolate [Na(PCO)(diox)0.5] also affords the complex [(dpp-bian)Al(OCP)(i-Pr2ImMe)] (5). Compounds have been characterized by IR and NMR spectroscopy and X-ray diffraction.