Synthesis, Crystal Structure, and Magnetic Properties of a Co Metal-organic Framework with Mixed Dicarboxylate and Tricarboxylate Ligands

One new mixed-ligand coordination polymer,namely[Co2（btc）（bpdc）（0.5）（py）3]n（1）,was hydrothermally synthesized using biphenyl-2,4,4＇-tricarboxylic acid（H3btc） as a main building block,along with two auxiliary ligands（H2bpdc = 2,2＇-bipyridine-5,5＇-dicarboxylic acid and py =pyridine）.The product 1 was characterized by IR spectroscopy,elemental,thermogravimetric,and single-crystal X-ray diffraction analyses.Single-crystal X-ray diffraction studies show that compound 1 possesses an intricate 3D metal-organic framework based on tetracobalt（Ⅱ） units.Magnetic susceptibility measurement indicates that compound 1 shows an antiferromagnetic coupling between the Co（Ⅱ） ions.

Synthesis and Structure of Dimolybdenum(I) Carbonyl Compound with Thiolate and Carboxylate Mixed-tri-bridging Ligands [Bu_4N][Mo_2(CO)_6(SC_6H_4Cl-p)_2(CF_3COO)]

The crystal of the title compound with formula C36H44Cl2F3Mo2NO8S2 (Mr = 10002.62) crystallized in monoclinic, space group P21/n, with a = 9.6184(1), b = 22.3476(2), c = 20.7758(2) ?, ( = 90.172(1)(, V = 4465.70(7) ?3, Z = 4, Dc = 1.491 g/cm3, F(000) = 2032, ( = 0.833 mm－1, Final R = 0.0665 and wR = 0.1650 for 5044 reflections with I >2.0( (I). The crystal structure revealed that the Mo2S2 core is planar, and the trifluoroacetic group acts as a bidentate bridging ligand and coordinates to two Mo atoms forming a five-membered ring plane, in which the Mo-Mo bond distance is 2.9222(9) ? and the O-C-O angle is 131.8(7)

Two-dimensional Grid-type Zinc(Ⅱ) Coordination Polymer Constructed by a New Aromatic Carboxylate Ligand

A new aromatic carboxylate ligand,namely 5-（pyrrolidin-1-yl）-1,3-benzenedicar-boxylic acid（H2pybdc）,was synthesized and characterized by FT-IR and single-crystal X-ray diffraction analysis.It crystallizes in triclinic system,P1 space group with a = 10.05（5） ,b = 11.53（5）,c = 12.92（6） ,α = 112.11（6）°,β = 92.79（7）°,γ = 102.98（7）°,V = 1337.113,Z = 4,Mr = 253.25,Dc = 1.258 g.cm-3,μ = 0.099 mm-1,F（000） = 536,the final R = 0.0822 and wR = 0.2575 for 1893 observed reflections（I 2σ（I））.Based on it,a two-dimensional grid-type Zn（Ⅱ） coordina-tion polymer of {[Zn（pybdc）（bpy）（H2O）].2H2O.0.5CH3OH}n（1） was solvothermally synthesized,which crystallizes in triclinic,space group P1 with a = 10.218（5） ？,b = 11.176（5） ,c =11.350（5） ,α = 95.855（5）°,β = 94.248（5）°,γ = 101.421（5）°,V = 1257.9（2） 3,Z = 2,Mr = 524.84,Dc = 1.386 g.cm-3,μ = 1.024 mm-1,F（000） = 546,the final R = 0.0635 and wR = 0.1879 for 3913 observed reflections（I 2σ（I））.

A Zn(II) Metal-organic Framework Consisting of Hexagonal Cavities Constructed by Benzyl-functionalized 5-Aminoisophthalate

The hydrothermal reaction of 5-benzylaminoisophthalic acid （H2BAIP） and Zn（CH3COO）2·2H2O in the presence of NaOH gave rise to a three-dimensional （3-D） metal-organic framework containing Zn（Ⅱ）-carboxylate chains, [Zn（BAIP）]n. Single-crystal X-ray diffraction analysis reveals that the complex crystallizes in trigonal space group R-3 with a = 28.354（2）, b = 28.354（2）, c = 8.3821（8） A, e = 120°, V= 5836.0（10） A^3, Z= 18, Mr = 334.62, Dc = 1.714 g·cm^3,μ = 1.909 mm^-1, S = 1.162, F（000） = 3060, the final R = 0.0785 and wR = 0.1121 for 2334 observed reflections （I 〉 2σ-（I））. Zn（Ⅱ） is in a distorted tetrahedral geometry, and BAIP serves as a μ4-bridge using two μ2,η^2-bridging carboxylate groups. BAIP links Zn（Ⅱ） ions into a 3-D network containing hexagonal cavities. The coordination-inert benzyl occupies the void space of the large hexagonal cavities. The complex is thermally stable up to 410℃, and exhibits photoluminescent emission at 522 nm on 402 nm excitation.

A Novel Three-dimensional Mn(Ⅱ) Coordination Polymer Constructed from Biphenyl-3,3',5,5'-tetracarboxylic Acid and Water

The title Mn（Ⅱ） coordination polymer,poly{[heptaaqua-（μ4-bi-phenyl-3,3？,5,5？-tetracarboxylate）-bimanganese（Ⅱ）] pentahydrate},[Mn_2（bpta）（H_2O）_7]_n·5n H_2O（I）,is crystallized from a mixture of biphenyl-3,3？,5,5？-tetracarboxylic acid（H_4bpta） and MnCl_2·4H_2O in waterethanol under room temperature. Its asymmetric unit consists of one and two halves of crystallographically independent Mn（Ⅱ） cations,one fully deprotonated H4 bpta ligand,seven coordinated water molecules and five solvent water as guest molecules. In I,each Mn（Ⅱ） atom is octahedrally coordinated by six oxygen atoms from bpta^（4-） anions and coordinated water molecules. In the Mn（Ⅱ） cations,one half Mn（Ⅱ） ion of them located at a 2-fold axis generating a trinuclear [Mn_3（H_2O）_2（RCOO）_2] linker by μ1,1-O（water） and μ1,3-O,O？（carboxylate） bridges and another half Mn（Ⅱ） ion with an inversion is a mononuclear linker. These neighbouring trinuclear and mononuclear Mn（Ⅱ） cations are linked together by biphenyl-3,3？,5,5？-tetracarboxylates to form a three-dimensional framework with a（42.84） topology of a（4,4）-connected net,in which the positions of the trinuclear [Mn_3（H_2O）_2（R-COO）_2] linker as a 4-connector linking four bpta^（4-） ligands in I reproduce an eagle-shaped arrangement. The polymeric structure exhibits a water channel with an accessible void of 797.1 ？~3,amounting to 15.7% of the total unit-cell volume. Each of the cavities in the network is occupied by solvent water molecules.

A Metal-organic Framework Containing Octanuclear Zn(Ⅱ) Clusters Constructed by 5-Methoxyisophthalate and Flexible Bis(imidazolyl) Ligand

The hydrothermal reaction of 5-methoxyisophthalic acid（MeO-H2ip）, 1,3-bis（2-methylimidazol-1-yl）propane（bmip） and Zn（NO3）2·6H2O in the presence of NaOCH3 gave rise to a three-dimensional（3-D） metal-organic framework containing octanuclear Zn（II） units, [Zn4（MeO-ip）3（OH）2（bmip）]n. Single-crystal X-ray diffraction analysis reveals that the complex crystallizes in the triclinic space group P1 with a = 11.348（3）, b = 14.163（4）, c = 15.088（4） , α = 108.537（2）, β = 106.542（2）, γ = 103.106（1）o, V = 2065.4（9） -3, Z = 2, Mr = 334.62, Dc = 1.740 g·cm-（-3）, μ = 2.375 mm-（-1）, S = 1.015, F（000） = 1096, the final R = 0.0272 and w R = 0.0715 for 8929 observed reflections（I 〉 2σ（I））. The complex is thermally stable up to 370 oC, and exhibits photoluminescent emission at 450 nm on 350 nm excitation.

Construction of Naphthalenediimide Lanthanide(Ⅲ)-MOFs and Composites Incorporated Electron-Rich Pyrene Derivative as Multifunctional Fluorescence Sensing for Nitro Aromatic Compounds and Aldehydes

The development of host-guest MOF luminescent composites has attracted considerable attention. However,it is still a challenge to reasonably design large scale conjugated polycarboxylic acids metal-organic framework (MOF) and modulate donor-acceptor interaction. Herein,a series of isostructural 3D porous lanthanide MOF [Ln_(2)(BINDI)0.5(NO_(3))(DMA)(H_(2)O)]∙DMA∙2.5H_(2)O (Ln = La (1),Ce (2),Pr (3) and Nd (4);H_(4)BINDI (N,N’-bis(5-isophthalic acid)-1,4,5,8-naphthalenediimide) were synthesized. Considering the electron-deficient performances of Ln-BINDI MOFs,D-A type composites Ln-MOFs (1—4@H_(4)TBAPy) were prepared via the incorporation of electron-rich H_(4)TBAPy (1,3,6,8-tetrakis(p-benzoic acid) pyrene),which more improved the luminescence performance of complexes 1—4 and can be used as fluorescence sensors for the detection of nitro compounds and aldehydes. High sensitivity of 1@H_(4)TBAPy towards pNBA,pNA PNP,DNP,and TNP could be achieved through hydrogen bond interactions between MOF and analytes,as well as the π-π interaction between H_(4)TBAPy and the naphthalene ring of BINDI,thus the fluorescence quenching efficiency of 1@H_(4)TBAPy was better than that of the complex 1. In addition,it is found that 1@H_(4)TBAPy has high selectivity and sensitivity to aromatic aldehyde SA,5-Mesal and HMBA. Such strategy to enhance the emission of NDI based Ln-BINDI MOFs,will open up an avenue to obtain more fluorescent MOFs for sensing.

Structural and optical properties of pillared Eu^(3+)-containing layered double hydroxides intercalated by 2-to 12-carbon aliphatic dicarboxylates

While the versatile composition of layered double hydroxides(LDHs)allows the introduction of almost any polyvalent cation in their structure,the exchangeable negatively charged ions intercalated between the plates increase their vast range of functionalities.Here we report on the preparation and optical properties of pillared Eu^(3+)-substituted ZnAl LDHs intercalated by aliphatic dicarboxylates:-OOC-(CH_(2))_(n-2)-COO-.The basal distance in these materials is dependent on the size and packing of the intercalated anions.By varying the number(n)of carbon atoms in the aliphatic chain from 2 to 12,the interlayer gallery of these ZnAlEu LDHs is considerably expanded from 0.9 to 2.1 nm.In the interlayer gallery,the aliphatic dicarboxylates form a monolayer,with the aliphatic chain inclined by an angleα≈63°with the hydroxide layers.The carbon atom in the COO-group is 0.43 nm far from the metal plane,showing that these carboxylates are not grafted in the brucite-like layers.These LDHs are thermally stable up to around 150℃,after which dehydroxylation of the hydroxide layers is observed.The Judd-Ofelt intensity parameters were obtained and compared to the Eu^(3+)-containing complexes with the same ligand series indicating a more symmetrical and less polarizable chemical environment around the rare earth ion.

Fe-Based Metal-Organic Frameworks:From Various Synthesis,Diverse Structures to Multifunctional Applications

Iron-based metal-organic frameworks(Fe-MOFs)have attracted extensive interest from researchers due to their tunability,favorable properties,and chemical versatility.Compared with conventional porous materials,Fe-MOFs exhibit better performance in a wide variety of applications.Herein,the structures of Fe-MOFs are summarized to explore potential structures based on isoreticular chemistry,as well as the recent research progress in their synthesis and multifunctional applications.The rapid development of Fe-MOFs has broadened the application range of Fe-MOFs,and a brief description of Fe-MOF applications in gas storage and separation,catalysis,bioimaging,and magnetism is outlined,with the aim to expand the prospects of Fe-MOFs in more practical applications.

An undecanuclear iron (Ⅲ) oxo-hydroxo aggregate with near nanometer size:Synthesis and crystal structure of[Fe_(11)O_6(OH)_6(O_2CPh)_3(O_2CPhMe-p)_(12)]

The tide compound is formed by controlled hydrolytic polymerization in nonaqueous solution of simple oxo-bridged binuclear ferric salts under the presence of carboxylate ligands. The rhombohedral crystalline form of the cluster with six imidazole molecules, which has crystallographically required C3v symmetry, will be reported. The largest Fe-Fe distance in the undecairon oxo-hydroxo cluster is about 0.68 nm and the cluster has a diameter near 2 nm, which implies that this cluster reaches a nanometer-sized dimension.