摘要：

The complexes Ln(L) 3 (L = N-(2,6-di-isopropylphenyl)-phenanthren- o-iminoquinone, Ln = Sc ( 1), Yb ( 2)) were synthesized by the reactions of phenanthren- o-iminoquinone L with scandium or ytterbium metals in benzene medium. The X-ray analysis revealed that the molecule of 2 consists of Yb 3+ cation coordinated by three phenanthren- o-iminosemiquinone ligands in η 2 fashion. Both complexes are paramagnetic. The magnetic moments of 1 (2.7 μ B) are consistent with the formulation Sc(L ) 3 (L = radical anion), in which spins on the individual units are uncoupled. The magnetic moments of 2 (3.7 μ B) indicate some antiferromagnetic coupling of paramagnetic centers in the molecules. The EPR spectrum of 1 in toluene exhibits a broad unresolved signal with g 2.0029 assigned to unpaired electrons of phenanthren- o-iminosemiquinone ligands. The reactions of phenanthren- o-iminoquinone L with NdI 2 and DyI 2 in benzene led to formation of iodide/phenanthren- o-iminoquinone complexes I 2Ln(L) 2 of Nd(III) ( 3) and Dy(III) ( 4). Besides, from the reaction with DyI 2 the product of partial disproportionation of 4 was isolated and identified as homoleptic complexes Dy(L) 3 ( 5), structure of which turned out identical to that of 2. The same reactions in ether or crystallization of 3 and 4 from ether yielded solvated complexes I 2Ln(L) 2(Et 2O) 2 (Ln = Nd ( 6), Dy ( 7)). The X-ray analysis of 6 and 7 has displayed unprecedented for iminoquinonates η 1 mode of metal–ligand coordination. Magnetic moments of 3, 4, 6 and 7 (3.3, 10.4, 3.4 and 10.6 μ β respectively) corresponding to μ eff of Nd(III) and Dy(III) suggest that in the compounds exists quick reversible intramolecular interligand electron transfer which results in diamagnetism of the total ligand system. Magnetic moment of 5 (12.8 μ B) corresponds to formulation of Dy 3+(L ) 3 with uncoupled spins of metal atom and the ligands.

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