Di- and trivalent lanthanide complexes stabilized by sterically demanding aminopyridinato ligands

Deprotonation of Ap(center dot)H {Ap(center dot)H = (2,6-diisopropylphenyl)-[6(2,4,6-triisopropylphenyl)pyridin-2-yl]amine} and Ap(center dot)H Ap(center dot)H = (2,6-diisopropylphenyl)-[6-(2,6-dimethylphenyl)pyridin-2-yl]amine) using KH leads to polymeric [Ap(center dot)K](n) and [Ap'K](n) which undergo clean salt metathesis reactions with NdCl3 in THF forming [Nd(Ap(center dot))Cl-2(THF)(2)](2) and [Nd(Ap')(2)Cl(THF)], respectively. Ethylene polymerization activities of the two chloro complexes (after activation with MAO) were studied. Derivatization of the chloro compounds proceeds without ate complex. formation, for instance the reaction of [Nd(Ap')(2)Cl(THF)] with one equiv. of [K(N(SiMe3)(2))] leads to the THF-free silylamide [Nd(Ap')(2)[N(SiMe3)(2)}]. Furthermore rare examples of heteroleptic amido-iodo complexes of selected divalent lanthanides can be stabilized by deprotonated Ap(center dot)H. Reaction of [Ap(center dot)K](n) with [LnI(2)(THF)(3)] (Ln = Yb, Sm) in THF leads, after workup in hexane, to [Yb(Ap(center dot))I(THF)(2)](2) and [Sm(Ap(center dot))l(THF)(2)](2). All lanthanide complexes, four of them are paramagnetic, were characterized by X-ray crystal structure analysis. These compounds exhibit an excellent solubility in nonpolar solvents like hexane. (c) Wiley-VCH Verlag GmbH D Co. KGaA, 69451 Weinheim, Germany, 2005.