Synthesis and structures of beta-diketoiminate complexes of magnesium

The reaction of the beta -diketoiminate lithium complex (dipp)NacNacLi . OE t2 ((dipp)NacNac = 2-((2,6-diisopropylphenyl)amino) -4- ((2,6-diisopropylph enyl)imino) -pent-2-enyl) with iPrMgCl and MgI2 yield the corresponding (di pp)NacNacMgiPr degrees OEt2 (1) and (dipp)NacNacMgI . OEt2 (2). The reactio n of 2 with NaBH4 in diethylether gives (dipp)NacNacMg(mu -H)(3)BH . OEt2 ( 3). The core element of compounds 1-3 is a six-membered ring formed by N(1) -C(1)-C(2)-C(3)-N(2) and magnesium. The structures of 1 and 2 show the beta -diketoiminate backbone in a boat-conformation with the tetrahedrally coor dinated metal center at the prow and the opposing carbon atom at the stern. The magnesium atom in 3 is octahedrally coordinated and out of the beta -d iketoiminate plane.