A novel 3D 4d–4f heterometallic coordination polymer: Synthesis, crystal structure and luminescence

A new type of heterogeneous catalysis strategy for organic reactions: Ugi-3CR catalyzed by highly stable MOFs with exposed carboxyl groups

A mild and highly efficient Ugi-3CR using a novel Cu-COOH@MOF-6 as the catalyst has been developed, which provides facile access to α-amino amides. The recycling test and XRD images showed that the catalytic system has good stability and recyclability.

Zr-MOF-808 as Catalyst for Amide Esterification

In this work, zirconium-based metal-organic framework Zr-MOF-808-P has been found to be an efficient and versatile catalyst for amide esterification. Comparing with previously reported homogeneous and heterogeneous catalysts, Zr-MOF-808-P can promote the reaction for a wide range of primary, secondary and tertiary amides with n-butanol as nucleophilic agent. Different alcohols have been employed in amide esterification with quantitative yields. Moreover, the catalyst acts as a heterogeneous catalyst and could be reused for at least five consecutive cycles. The amide esterification mechanism has been studied on the Zr-MOF-808 at molecular level by in situ FTIR spectroscopic technique and kinetic study.

A series of lanthanide–quinoxaline-2,3(1H,4H)-dione complexes containing 1D chiral Ln2O3 (Ln = Eu, Tb, Sm, Dy) chains: luminescent properties and response to small molecules

A series of isostructural lanthanide–quinoxaline-2,3(1H,4H)-dione containing 1D chiral chains shows high sensing effect toward the small solvent molecules, in which tertiary butanol was an excellent sensitizer, while tetrahydrofuran was a highly quenching species.

Metal-organic frameworks: versatile heterogeneous catalysts for efficient catalytic organic transformations

Novel catalytic materials are highly demanded to perform a variety of catalytic organic reactions. MOFs combine the benefits of heterogeneous catalysis like easy post reaction separation, catalyst reusability, high stability and homogeneous catalysis such as high efficiency, selectivity, controllability and mild reaction conditions. The possible organization of active centers like metallic nodes, organic linkers, and their chemical synthetic functionalization on the nanoscale shows potential to build up MOFs particularly modified for catalytic challenges. In this review, we have summarized the recent research progress in heterogeneous catalysis by MOFs and their catalytic behavior in various organic reactions, highlighting the key features of MOFs as catalysts based on the active sites in the framework. Examples of their post functionalization, inclusion of active guest species and metal nanoparticles have been discussed. Finally, the use of MOFs as catalysts for asymmetric heterogeneous catalysis and stability of MOFs has been presented as separate sections.

Ln-Ag heterometallic coordination polymers

The last few years have seen an increasing interest in the study of lanthanide-silver (Ln-Ag) heterometallic coordination polymers due to their potential applications. It has led to intense activity of chemists to produce Ln-Ag heterometallic coordination polymers and investigate their properties. In this review, we summarize recent research development in the fascinating and challenging field of Ln-Ag heterometallic coordination polymers. This review covers 182 Ln-Ag heterometallic coordination polymers, which are categorized by the kind of ligand as N-heterocyclic carboxylate ligands and others. There are three categories of Ln-Ag coordination polymer based on N-heterocyclic carboxylate ligands: one dimensional (1D), 2D, and 3D. The 3D part was divided into Ln-Ag coordination polymers based on pyridine carboxylate ligands and other N-heterocyclic carboxylate ligands. This perspective illustrates the coordination features of compounds constructed by N-heterocyclic carboxylate ligands. Luminescent properties are also discussed.

2-D lanthanide–organic complexes constructed from 6,7-dihydropyrido(2,3-d)pyridazine-5,8-dione: synthesis, characterization and photoluminescence for sensing small molecules

The 2-D lanthanide–organic complex [(EuHPDH)(ox)(H₂O)]_n, synthesized under hydrothermal conditions, shows high potential for sensing small molecules by its luminescence properties in different emulsions.

Luminescence tuning and white-light emission of co-doped Ln-Cd-organic frameworks

Four new three-dimensional isostructural lanthanide-cadmium metal-organic frameworks (Ln-Cd MOFs), [LnCd(2)(imdc)(2)(Ac)(H(2)O)(2) ]·H(2)O (Ln=Pr (1), Eu (2), Gd (3), and Tb (4); H(3)imdc=4,5-imidazoledicarboxylic acid; Ac=acetate), have been synthesized under hydrothermal conditions and characterized by IR, elemental analyses, inductively coupled plasma (ICP) analysis, and X-ray diffraction. Single-crystal X-ray diffraction shows that two Ln(III) ions are surrounded by four Cd(II) ions to form a heteronuclear building block. The blocks are further linked to form 3D Ln-Cd MOFs by the bridging imdc(3-) ligand. Furthermore, the left- and right-handed helices array alternatively in the lattice. Eu-Cd and Tb-Cd MOFs can emit characteristic red light with the Eu(III) ion and green light with the Tb(III) ion, respectively, while both Gd-Cd and Pr-Cd MOFs generate blue emission when they are excited. Different concentrations of Eu(3+) and Tb(3+) ions were co-doped into Gd-Cd/Pr-Cd MOFs, and tunable luminescence from yellow to white was achieved. White-light emission was obtained successfully by adjusting the excitation wavelength or the co-doping ratio of the co-doped Gd-Cd and Pr-Cd MOFs. These results show that the relative emission intensity of white light for Gd-Cd:Eu(3+),Tb(3+) MOFs is stronger than that of Pr-Cd:Eu(3+),Tb(3+) MOFs, which implies that the Gd complex is a better matrix than the Pr complex to obtain white-light emission materials.

Solvothermal synthesis, crystal structure, and properties of lanthanide-organic frameworks based on thiophene-2,5-dicarboxylic acid

A series of lanthanide-organic framework coordination polymers, {[La(2)(TDC)(2)(NO(3))(H(2)O)(4)](OH)·5H(2)O}(n) (1) and [Ln(TDC)(NO(3))(H(2)O)](n) (TDC = thiophene- 2, 5- dicarboxylic acid; Ln = Nd(2), Sm(3), Eu(4), Gd(5), Tb(6), Dy(7), Ho(8), Er(9), Yb(10)) have been synthesized by solvothermal reaction and characterized by elemental analysis, FT-IR, TG analysis, single-crystal X-ray diffraction and power X-ray diffraction. The single-crystal X-ray diffraction analysis results show that 1 displays a 3-D porous framework with (3,7)-connected {4(10).6(11)}{4(3)} topology. The compounds 2-10 crystallized in the same P2(1)/c space group and exhibits a (3,6)-connected {4.6(2)}(2){4(2).6(10).8(3)} topology, Right-handed and left-handed helical chains coexist in the 2-D layer structure. The luminescence properties of 2-10 and the magnetic properties of 5,7,8,9 were investigated.

A series of lanthanide-organic polymers incorporating nitrogen-heterocyclic and aliphatic carboxylate mixed-ligands: structures, luminescent and magnetic properties

Seven new lanthanide-organic coordination polymers incorporating both nitrogen heterocyclic dicarboxylate and various auxiliary ligands, {[Ln(3)(Hpimda)(4)(mu(2)-HCOO).5H(2)O].H(2)O}(n)} Ln = Sm (1), Ln = Eu (2), Ln = Gd (3), Ln = Dy (4), Ln = Ho (5), {[Ce(2)(Hpimda)(2)(mu(4)-C(2)O(4)).8H(2)O].2H(2)O}(n) (6), {[Yb(2)(pyda)(mu(4)-C(2)O(4))(2).4H(2)O].3H(2)O}(n) (7) (H(3)pimda = 1H-2-propyl-4,5-imidazoledicarboxylic acid, H(2)pyda = 2,6-pyridinedicarboxylic acid) have been fabricated successfully and characterized systematically. Complexes 1-5 are isomorphous and isostructural, and are built from two-dimensional (2-D) double-decker networks based on the tetranuclear basic carboxylate as a secondary building unit (SBU). Both polymers 6 and 7 feature a (3,4)-connected 3-D framework consisting of 2-D lanthanide-organic hexagonal grids, which are further interlinked via the mu(4)-oxalate ligand. The results of magnetic determination show the same end-to-end bridging fashion of formate group results in different magnetic properties occurring between lanthanide centers. The luminescence emission spectra of the complexes vary depending on the lanthanide ion present.