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The development of a convenient method for the discrimination of typically quenching metal ions such as Cu2+, Co2+, Ni2+, and Fe3+ is of great interest but still a challenge. By simultaneously incorporating Eu3+ and organic dye 3,3′‐diethyloxacarbocyanine iodide (DOC) into a metal‐organic framework, MOF‐253, a luminescent sensor array MOF‐253⊃Eu3++DOC with three emission centers is generated. Utilizing the diversity of quenching responses of metal ions to the different emission centers, five metal ions including Ag+, Cu2+, Fe3+, Co2+ and Ni2+ can be well distinguished with a discrimination accuracy of 100% at a concentration as low as 60 µm. Subsequently, the binary and ternary mixtures of three metal ions (Fe3+, Co2+, and Ni2+) can also be discriminated successfully. Furthermore, taking Cu2+ and Ag+ as examples, this MOF‐based sensor array can quantify the ion concentration at a low range from 0 to 15 µm. Most probably, this is the first case of simultaneous recognition and quantitation of metal ions in an aqueous solution using an MOF‐based luminescent sensor array. Since a variety of luminescent species including organic dyes and lanthanide ions can be introduced into MOFs to generate multiple‐dimensional luminescence, such strategy will open a new avenue for luminescent sensor assays.

Treatment of 6‐R‐2‐(Me3SiCH2)C5H3N (R = H or Me) with nBuLi in diethyl ether affords the dimeric lithium complexes [{2‐(6‐R‐Pyr)(Me3Si)}CHLi·OEt2]2 (Pyr = pyridine, C5H3N) in high yields. In these complexes, the two anionic ligands have different bonding modes. These complexes easily undergo insertion reactions with nitriles to form six‐membered cyclic dimeric complexes in good yields. Further transmetalations of the six‐membered cyclic complexes with CuCl, SnCl4, or CoCl2 allow the formation of new metal complexes that maintain the frameworks of the six‐membered metallacycles. All complexes represented above were fully characterized by methods including single‐crystal X‐ray crystallography. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Temperature sensing plays essential roles in both fundamental research and high-tech applications. In this work, three isomorphic hexanuclear lanthanide metal-organic frameworks (Ln-MOFs), Ln(BPDC-xN) (Ln = Eu3+/Tb3+, x = 0, 1,...

Numerous luminescent metal-organic frameworks (LMOFs) with desired functionalized ligands often suffer from solid-state fluorescence quenching, which greatly restricts their practical applications. The multivariate LMOFs and isolated-ligand strategy provide an effective...