A series of Zn(II) and Cd(II) metal−organic frameworks, namely, [Zn(DFDA)] (1), [Cd(DFDA)(C2H5OH)] (2), [Zn2(DFDA)2(L1)2]2·3H2O (3), [Cd2(DFDA)2(L1)2] (4), [Zn(DFDA)(L2)] (5), [Cd(DFDA)(L2)(DMF)] (6), and [Zn(DFDA)(L3)] (7) (where DFDA = 9,9-dipropylfluorene-2,7-dicarboxylate anion, L1 = 1,4-bis(imidazol-1-ylmethyl)benzene, L2 = 1,1′-(1,4-butanediyl) bis(imidazole), L3 = 2,2′-bipyridine) have been synthesized under hydrothermal conditions and structurally characterized. Compound 1 exhibits a three-dimensional (3D) framework containing one-dimensional (1D) Zn(II)-O clusters, with (48·67) topology. Compound 2 contains hydrophobic channels built from infinite 1D Cd(II)-O clusters, with (48·54·63) topology. Compounds 3 and 4 possess isomorphic two-dimensional (2D) layer structures which contain two kinds of rings, and the layers interdigitate extensively. Compound 5 features a 3D diamond-like structure that contains four interpenetrating networks. Compound 6 displays a 2D (4,4) topology. Compound 7 is composed of 1D zigzag chains that are entangled through π−π stacking interactions to generate three interpenetrating diamond-like networks. The potential of ligand H2DFDA to produce interesting metal−organic frameworks is investigated. In particular, the effects of the coordination modes of carboxylates on the formation of different frameworks are evaluated. Thermogravimetric analyses (TGA) for these compounds are discussed. Luminescent studies show that 1−7 exhibit strong blue fluorescent emissions.

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The amine-elimination reactions of Ln[N(SiMe3)2]2(THF)2(Ln=Sm, Yb and Eu) with amine bis(phenol)s (L1H2=[BunN(CH(2)-2-OC6H(2)-3,5-But2)2]H2; L2H2=[Me2NCH2CH2N(CH(2)-2-OC6H(2)-3,5-But2)2]H2) were investigated. It was found that the number of heteroatom(s) in the ligands has a profound effect on the reaction outcome for the samarium systems. Reaction of the tetradentate diamino-bis(phenol)s L2H2 with Sm[N(SiMe3)2]2(THF)2 afforded a yellow solution, which indicated the complete oxidation of the SmII species, yellow being the characteristic color of SmIII species, while the same reaction with Eu[N(SiMe3)2]2(THF)2 gave a divalent complex with a dimeric structure (EuL2)2. Using the tridentate amine bis(phenol)s L1H2 as the reagent, the novel mixed-valent samarium complex SmIII2SmIIL1(4) was prepared by the same reaction. Both reactions of L1H2 with Yb[N(SiMe3)2]2(THF)2 and Eu[N(SiMe3)2]2(THF)2 yielded the normal divalent lanthanide complexes: monomeric complex for YbII, YbL1(THF)3 and dimeric complex for EuII, (EuL1)2. All of the complexes are well characterized with elemental analyses, IR and 1H NMR spectra for , and , as well as X-ray crystal structure determination in the cases of complexes , , and .