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Glutathione (GSH) in tumors consumes 1O2 and seriously inhibits the PDT effect. MnO2-coated porphyrin metal-organic frameworks are developed to realize the oxidation of GSH by MnO2 for enhanced PDT, activated MR imaging, and controllable release of DOX as magnetic resonance imaging guided drug-PDT dual-therapy.

Utilization of N,N‐dimethylformamide (DMF) as an amine source and reductant for synthesizing tertiary amines is a promising way to replace the substrates formaldehyde and dimethylamine, and it is desirable to seek porous acid‐resistant catalysts for heterogeneous catalysis of this reaction. Herein, a robust metal–organic framework (MOF) {[Th6O4(OH)4(H2O)6(BCP)3]⋅10 DMF}n (1) containing stacked nanocages with a diameter of 1.55 nm was constructed. Compound 1 can maintain its single‐crystal structure even kept in air at 400 °C for 3 h, and in DMF or water at 200 °C for 7 days. Density functional theory (DFT) calculations suggested that the high interaction energy between the [Th6O4(OH)4(H2O)6]12+ clusters and ligands was responsible for the excellent stability of 1. Catalytic investigations revealed that 1 can effectively and size‐selectively catalyze the reductive amination of aldehydes with DMF, and it can be reused at least five times without obvious loss in catalytic activity. [ABSTRACT FROM AUTHOR]

Regulating Lewis acid–base sites in catalysts to investigate their influence in the chemical fixation of CO2 is significant but challenging. A metal–organic framework (MOF) with open metal Co sites, {(NH2Me2)[Co3(μ3‐OH)(BTB)2(H2O)]⋅9 H2O⋅5 DMF}n (1), was obtained and the results of the catalytic investigation show that 1 can catalyze cycloaddition of CO2 and aziridines to give 99 % yield. The efficiency of the cyclization of CO2 with propargyl amines is only 32 %. To improve the catalytic ability of 1, ligand XN with Lewis base sites was introduced into 1 and coordinated with the open Co sites, resulting in a decrease of the Lewis acid sites and an increase in the Lewis base sites in a related MOF 2 ({(NH2Me2)[Co3(μ3‐OH)(NHMe2)(BTB)2(XN)]⋅8 H2O⋅4 DMF}n). Selective regulation of the type of active centers causes the yield of oxazolidinones to be enhanced by about 2.4 times, suggesting that this strategy can turn on/off the catalytic activity for different reactions. The catalytic results from 2 treated with acid solution support this conclusion. This work illuminates a MOF‐construction strategy that produces efficient catalysts for CO2 conversion. [ABSTRACT FROM AUTHOR]

A three-dimensional metal–organic framework, namely {[Zn3(BIBT)(BTC)5/3(μ3-OH)]·solvents}n (JXUST-4), has been synthesized by using ZnII ions, and BIBT and H3BTC ligands (BIBT = 4,7-bi(1H-imidazol-1-yl)benzo-[2,1,3]thiadiazole and H3BTC = 1,3,5-benzenetricarboxylic acid). JXUST-4 shows a new (3,3,7)-connected topology net containing a trinuclear ZnII cluster, uncoordinated N atoms of BIBT and uncoordinated carboxylate O atoms of H3BTC, which facilitates the interaction between the framework and analytes. Fluorescence studies indicate that JXUST-4 generates light yellow luminescence, which could be ascribed to ligand-centered emission. More importantly, JXUST-4 could be viewed as an effective fluorescent sensor toward acetylacetone through an obvious fluorescence red-shift with high sensitivity, efficient selectivity, and outstanding recycling capacity. Furthermore, the possible sensing mechanism of JXUST-4 toward acetylacetone is due to electron transfer and weak interactions between the analyte and framework. [ABSTRACT FROM AUTHOR]

A new metal‐organic framework (MOF) {[Cd2(bbib)2(ndc)2]⋅2DMF}n (JXUST‐1) (bbib=1,3‐bis(benzimidazolyl)benzene, H2ndc=1,4‐naphthalenedicarboxylic acid, DMF=N,N‐dimethylformamide) has been solvothermally synthesized and characterized by single‐crystal X‐ray diffraction, PXRD, TGA, IR and elemental analysis. JXUST‐1 exhibits a three‐dimensional 6‐connected pcu topology with a Schläfli symbol {412.63} constructed by [Cd2(CO2)3] secondary building units. Fluorescence studies show that this MOF can sensitively and selectively recognize Al3+ via a fluorescence enhancement effect, and the detection limit is 0.048 ppm. Furthermore, JXUST‐1 displays relatively good thermal and chemical stabilities as well as reusability. All these results suggest JXUST‐1 to be a highly selective and recyclable luminescent sensing material for the detection of Al3+. [ABSTRACT FROM AUTHOR]

A new metal‐organic framework (MOF) {[Cd2(bbib)2(ndc)2]⋅2DMF}n (JXUST‐1) (bbib=1,3‐bis(benzimidazolyl)benzene, H2ndc=1,4‐naphthalenedicarboxylic acid, DMF=N,N‐dimethylformamide) has been solvothermally synthesized and characterized by single‐crystal X‐ray diffraction, PXRD, TGA, IR and elemental analysis. JXUST‐1 exhibits a three‐dimensional 6‐connected pcu topology with a Schläfli symbol {412.63} constructed by [Cd2(CO2)3] secondary building units. Fluorescence studies show that this MOF can sensitively and selectively recognize Al3+ via a fluorescence enhancement effect, and the detection limit is 0.048 ppm. Furthermore, JXUST‐1 displays relatively good thermal and chemical stabilities as well as reusability. All these results suggest JXUST‐1 to be a highly selective and recyclable luminescent sensing material for the detection of Al3+. [ABSTRACT FROM AUTHOR]

Glutathione (GSH) in tumors consumes 1O2 and seriously inhibits the PDT effect. MnO2-coated porphyrin metal–organic frameworks are developed to realize the oxidation of GSH by MnO2 for enhanced PDT, activated MR imaging, and controllable release of DOX as magnetic resonance imaging guided drug–PDT dual-therapy. [ABSTRACT FROM AUTHOR]

Abstract: Three Gd‐based metal‐organic frameworks with the formulas of {[Gd2(suc)3(H2O)2]⋅H2O}∞ (1), {[Gd2(fum)3(H2O)4]⋅2H2O}∞ (2) and [Gd(glu)(ox)0.5(H2O)2]∞ (3) (suc=succinate, fum=fumarate, glu=glutarate and ox=oxalate) have been hydro/solvothermally synthesized through the reaction of Gd2O3 and dicarboxylate ligands. Complexes 1 and 2 take three‐dimensional (3D) structures derived from carboxylate‐bridged chains, while complex 3 presents a Zigzag chain‐based two‐dimensional (2D) structure. All of them exhibit relatively good thermal stabilities. Magnetic investigations indicate that complexes 1−3 reveal weak magnetic interactions between the neighbouring GdIII ions. Moreover, they display large magnetic entropy changes with −ΔSmmax reaching 42.22 J kg−1 K−1 (1), 37.97 J kg−1 K−1 (2) and 39.15 J kg−1 K−1 (3) with ΔH=7 T, respectively, indicating that they are promising cryogenic magnetorefrigerants. [ABSTRACT FROM AUTHOR]

Abstract Three zinc(II) metal-organic frameworks have been solvothermally synthesized with V-shaped 1,3-bis(1-imidazolyl)benzene (bib) and 4,4'-oxydibenzoic acid (4,4'-H 2 oba), namely {[Zn(bib)(oba)]⋅solvents} n (1), {[Zn(bib)(oba)]·2H 2 O} n (2) and {[Zn 2 (bib) 2 (oba) 2 ]⋅2EtOH⋅H 2 O} n (3). All of them are characterized by single-crystal X-ray diffraction, infrared spectra and powder X-ray diffraction. Complex 1 presents a two-fold interpenetrating three-dimensional structure with 4-connected (65.8) topology. While, complexes 2 and 3 exhibit double layer cavity and double chains based two-dimensional structure, respectively. Luminescent studies indicate that 2 and 3 display selectively sensitive to electron-deficient nitroaromatic explosives with excellent anti-interference abilities. Graphical abstract Three zinc(II) metal-organic frameworks have been synthesized by the regulation of temperature- and solvent. Complexes 2 and 3 show selectively sensitive to electron-deficient nitroaromatic explosives with excellent anti-interference abilities. fx1 Highlights • Complexes 1 – 3 exhibit 2D/3D structures derived from V-shaped bib and H 2 oba with different conformations. • Through the change of reaction conditions, the assembly of MOFs with novel structures and interesting properties has been successfully realized. • Complexes 2 and 3 exhibit selectively sensitive to electron-deficient nitroaromatic explosives with high anti-interference abilities. [ABSTRACT FROM AUTHOR]