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Three new heterometallic coordination polymers formulated as {[Ca(CuL)(H2O)5]·H2O}n (1), [Sr(CuL)(H2O)2]n (2), and [Ba(CuL)(H2O)4]n (3) have been obtained by reaction of a rigid metalloligand [CuL]2− (H4L = N-5-sulfosalicylideneglycylglycine) with the corresponding alkaline earth metal cations M2+ (M = Ca, Sr or Ba). Their crystal structures are determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses and IR spectra. The coordination preferences of the alkaline earth metal cations are found to have pronounced effects on the structural topologies. Complex 1 has a distorted ladder-like one-dimensional (1D) structure. In complex 2, Sr(ii) ions link metalloligands [CuL]2−via the sulfonate and carbonyl oxygen atoms to generate a three-dimensional (3D) framework. Complex 3 is arranged in a 3D framework formed by the linkage of copper(ii) and barium(ii) via carboxylate and sulfonate bridges. Variable-temperature magnetic susceptibility studies indicate that all the complexes exhibit weak antiferromagnetic interactions between the Cu(ii) paramagnetic centers. [ABSTRACT FROM AUTHOR]

The reactions of ytterbium dichlorides with different β-diketiminate ligand ((Ar)NC(Me)CHC(Me)N(Ar′), Ar=Ar′=C6H5 (L1); Ar=Ar′=2,6-Me2&z.sbnd;C6H3 (L2); Ar=C6H5, Ar′=2,6-Pr2i-C6H3 (L3)) with 1 equiv of Cp′Na were studied. It was found that the bulkiness of β-diketiminate ligand and cyclopentadienyl group both have significant effect on the above reaction. For less bulky ligands L1 and L2, the reaction affords not the expected mixed-ligand ytterbium chloride, (C5H5)YbLCl or (CH3C5H4)YbCl, but the ligand-redistributed product (C5H5)2YbL or (CH3C5H4)2YbL. For bulkier ligand L3, the desired anionic ytterbium chloride (C5H5)YbL3(μ-Cl)2Li(THF)2 is obtained. For the smallest ligand L1, the expected ytterbium monochloride can also be obtained using bulky C5Me5Na as reactant. Each of these complexes was well characterized, while several have been characterized by X-ray diffraction structure determination. [Copyright &y& Elsevier]

Attempted synthesis of sterically demanding tris-β-diketiminate complexes of europium led to oxidation–coupling of β-diketiminates and the formation of the THF-solvated divalent europium complex Eu(L2,6-Me2)2(THF) (L2,6-Me2= [{N(2,6-Me2C6H3)C(Me)}2CH]−), while the normal tris-β-diketiminate complex Eu(L2-Me)3for the less bulky ligand L2-Me([{N(2-MeC6H4)C(Me)}2CH]−) was isolated by the same procedure. [ABSTRACT FROM AUTHOR]

A novelbinuclear ytterbium(II) complex supported by a naphthalene-bridgedbis(guanidinate) ligand, [Yb(μ-L)(THF)]2(1; L = 1,8-C10H6{NC(NiPr)(NHiPr)}2), was synthesizedby the reduction reaction of [Yb(L)Cl(THF)2] with Na/Kalloy in THF and structurally characterized. The reactions of 1with CH3CN and p-ClC6H4CH2CN resulted in the formation of the correspondingbinuclear (crotononitrileamido)ytterbium(III) complexes [Yb(L)(μ(N,N′)-N(H)C(Me)C(H)CN)(THF)]2(2) and [Yb(L)(μ(N,N′)-N(H)C(CH2C6H4-p-Cl)C(C6H4-p-Cl)CN)(THF)]2(3) viametalation of the nitrile, followed by insertion of a second nitrilemolecule. Treatment of 1with the bulkier Ph2CHCN afforded the mononuclear (keteniminato)ytterbium(III) complex[Yb(L)(NCCPh2)(THF)2] (4) by deprotonation of Ph2CHCN. The molecular structuresof 2–4have been determined. [ABSTRACT FROM AUTHOR]