Synthesis and Structural Characterization of Homoleptic 1,2,4-Diazaphospholide Alkaline Earth Metal Complexes

Abstract

The alkaline earth metal complexes [(η2-3,5-tBu2dp)(μ-Mg)(η1:η1-3,5-tBu2dp)]2 (2), {[(η2-3,5-tBu2dp)(μ-η2:η5-3,5-tBu2dp)(μ-η2:η1-3,5-tBu2dp)Ca]2(μ-Ca)} (3), [Sr(3,5-tBu2dp)2]m (4), [Ba(3,5-tBu2dp)2)]n (5), and [η1-{H(3,5-tBu2dp)}2Ca(η2-3,5-tBu2dp)2] (6), bearing bulky 1,2,4-diazaphospholide ligands [3,5-tBu2dp]− ([3,5-tBu2dp]− = 3,5-di-tert-butyl-1,2,4-diazaphospholide), were prepared. The structures of magnesium and calcium 1,2,4-diazaphospholide complexes represent homoleptic 1,2,4-diazaphospholide alkaline earth metal oligomers with a novel array of metal–ligand binding modes.