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Three new three-dimensional (3D) metal-organic frameworks [M 2 (ttdc) 2 (dabco)] (M = Zn(II), 1-Zn; Cu(II), 1-Cu; and Zn/Cu, 1-ZnCu) based on thieno[3,2- b ]thiophene-2,5-dicarboxylate (ttdc 2- ) were synthesized and characterized by a combination of physicochemical methods (single crystal X-ray diffraction, powder X-ray diffraction, chemical and thermogravimetric analyses and IR spectroscopy). 1-Cu demonstrated permanent porosity ( V pore = 0.790 cm 3 g -1 and S BET = 1725 m 2 g -1 ) and significant CO 2 , CH 4 , C 2 H 2 , C 2 H 4 and C 2 H 6 gas uptakes under ambient conditions. The adsorption selectivities for gas mixtures, calculated by IAST, were 10.8 (10.7), 14.6 (9.4), 1.7 (1.6) and 1.5 (1.6) for the equimolar gas mixture compositions CO 2 /N 2 , C 2 H 6 /CH 4 , C 2 H 6 /C 2 H 4 and C 2 H 6 /C 2 H 2 at 1 bar and 273 K (298 K), respectively. The mixed-metal compound 1-ZnCu was prepared by a crystal-to-crystal ion exchange metathesis reaction from 1-Zn with a 52% degree of ion substitution, confirmed by energy-dispersive X-ray spectroscopy, optical microscopy and single crystal X-ray diffraction analysis.

A new 3D metal-organic framework {[Cd 16 (tr 2 btd) 10 (dcdps) 16 (H 2 O) 3 (EtOH)]∙15DMF} n (MOF 1, tr 2 btd = 4,7-di(1,2,4-triazol-1-yl)benzo-2,1,3-thiadiazole, H 2 dcdps = 4,4'-sulfonyldibenzoic acid) was obtained and its luminescent properties were studied. MOF 1 exhibited bright blue-green luminescence with a high quantum yield of 74 % and luminescence quenching response to a toxic natural polyphenol gossypol and luminescence enhancement response to some trivalent metal cations (Fe 3+ , Cr 3+ , Al 3+ and Ga 3+ ). The limit of gossypol detection was 0.20 µM and the determination was not interfered by the components of the cottonseed oil. The limit of detection of gallium(III) was 1.1 µM. It was demonstrated that MOF 1 may be used for distinguishing between the genuine sunflower oil and oil adulterated by crude cottonseed oil through qualitative luminescent and quantitative visual gossypol determination., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Here, we present a series of Cd(II) coordination polymers containing two types of ligands: sterically rigid terephthalate derivatives (bdc-NO 2 2- and bdc-Br 2- ) and flexible bis(2-methylimidazolyl)propane (bmip). The combination of two types of ligands is used to obtain and characterize compounds by single crystal and powder X-ray diffraction, FT-IR, elemental analysis, and TGA. Guest exchange results in structural transformations. 2-fold interpenetrated 1 ·DMF and 2 ·DMF rapidly undergo to 4-fold interpenetrated 1 ·Et 2 O, 1 ·EtOH, and 1 ·H 2 O, or 2 ·Et 2 O, respectively. Also, changes in the coordinating numbers and length of the N , N '-donor bmip ligand were observed according to single crystal X-ray analysis. Activated guest-free compounds [Cd(bdc-NO 2 )(bmip)] ( 1 ) and [Cd(bdc-Br)(bmip)] ( 2 ) are shown to be porous with a BET surface area of 103 and 283 m 2 ·g -1 , respectively. Moreover, both compounds demonstrate gate-opening behavior of ethylene adsorption isotherms at low pressures (<1 bar) and highly selective adsorption of benzene over cyclohexane or lower alcohols. Also, both compounds demonstrate a strong dependence of the maximum of the photoluminescence emission on an excitation wavelength. As a result, the photoluminescence color changes from white to red and from blue to red through green and yellow for compounds 1 and 2 , respectively, with excitation wavelength changing from 360 to 540 nm.

We report on the design of 1D MOFs based on a nopinane-annelated organic ligand and Co(II) or Ni(II), the variation of which allows tuning the optical modulation bandwidth. Structural and time-resolved analysis revealed the optical modulation mechanism, the rates and its endurance, thereby enriching the list of sustainable MOFs for tunable optical modulators.

Exploiting 2-(alkylsulfonyl)pyridines as 1,3-N,S-ligands, herein we have constructed 1D CuI-based coordination polymers (CPs) bearing unprecedented (CuI) n chains and possessing remarkable photophysical properties. At room temperature, these CPs show efficient TADF, phosphorescence or dual emission in the deep-blue to red range with outstandingly short decay times of 0.4-2.0 μs and good quantum performance. Owing to great structural diversity, the CPs demonstrate a variety of emissive mechanisms, spanning from TADF of 1 (M + X)LCT type to 3 CC and 3 (M + X)LCT phosphorescence. Moreover, the designed compounds emit strong X-ray radioluminescence with the quantum efficiency of up to an impressive 55% relative to all-inorganic BGO scintillators. The presented findings push the boundaries in designing TADF and triplet emitters with very short decay times.

We introduce here a new subclass of copper(I) hybrid emitters simultaneously containing [Cu x I y ] z - anions and Cu + cations, separated in space by a Janus head ligand. When UV-irradiated at 298 K, these unique "Two-In-One" hybrids exhibit a short-lived green TADF with near-unity quantum yield and a strong solvatochromic effect. Moreover, they manifest a strong radioluminescence upon X-ray irradiation. These findings open up new possibilities for the design of highly performing TADF materials.

Five new metal-organic frameworks based on Mn(II) and 2,2'-bithiophen-5,5'-dicarboxylate (btdc 2- ) with various chelating N-donor ligands (2,2'-bipyridyl = bpy; 5,5'-dimethyl-2,2'-bipyridyl = 5,5'-dmbpy; 4,4'-dimethyl-2,2'-bipyridyl = 4,4'-dmbpy) [Mn 3 (btdc) 3 (bpy) 2 ]·4DMF, 1 ; [Mn 3 (btdc) 3 (5,5'-dmbpy) 2 ]·5DMF, 2 ; [Mn(btdc)(4,4;-dmbpy)], 3 ; [Mn 2 (btdc) 2 (bpy)(dmf)]·0.5DMF, 4 ; [Mn 2 (btdc) 2 (5,5'-dmbpy)(dmf)]·DMF, 5 (dmf, DMF = N,N-dimethylformamide) have been synthesized, and their crystal structure has been established using single-crystal X-ray diffraction analysis (XRD). The chemical and phase purities of Compounds 1 - 3 have been confirmed via powder X-ray diffraction, thermogravimetric, and chemical analyses as well as IR spectroscopy. The influence of the bulkiness of the chelating N-donor ligand on the dimensionality and structure of the coordination polymer has been analyzed, and the decrease in the framework dimensionality, as well as the secondary building unit's nuclearity and connectivity, has been observed for bulkier ligands. For three-dimensional (3D) coordination polymer 1 , the textural and gas adsorption properties have been studied, revealing noticeable ideal adsorbed solution theory (IAST) CO 2 /N 2 and CO 2 /CO selectivity factors (31.0 at 273 K and 19.1 at 298 K and 25.7 at 273 K and 17.0 at 298 K, respectively, for the equimolar composition and the total pressure of 1 bar). Moreover, significant adsorption selectivity for binary C 2 -C 1 hydrocarbons mixtures (33.4 and 24.9 for C 2 H 6 /CH 4 , 24.8 and 17.7 for C 2 H 4 /CH 4 , 29.3 and 19.1 for C 2 H 2 /CH 4 at 273 K and 298 K, respectively, for the equimolar composition and the total pressure of 1 bar) has been observed, making it possible to separate on 1 natural, shale, and associated petroleum gas into valuable individual components. The ability of Compound 1 to separate benzene and cyclohexane in a vapor phase has also been analyzed based on the adsorption isotherms of individual components measured at 298 K. The preferable adsorption of C 6 H 6 over C 6 H 12 by 1 at high vapor pressures ( V B / V CH = 1.36) can be explained by the existence of multiple van der Waals interactions between guest benzene molecules and the metal-organic host revealed by the XRD analysis of 1 immersed in pure benzene for several days ( 1≅ 2 C 6 H 6 ). Interestingly, at low vapor pressures, an inversed behavior of 1 with preferable adsorption of C 6 H 12 over C 6 H 6 ( K CH / K B = 6.33) was observed; this is a very rare phenomenon. Moreover, magnetic properties (the temperature-dependent molar magnetic susceptibility, χ p ( T ) and effective magnetic moments, μ eff ( T ), as well as the field-dependent magnetization, M ( H )) have been studied for Compounds 1 - 3 , revealing paramagnetic behavior consistent with their crystal structure.

1 H -Imidazole derivatives establish one of the iconic classes of ESIPT-capable compounds (ESIPT = excited state intramolecular proton transfer). This work presents the synthesis of 1-hydroxy-4-(2-hydroxyphenyl)-5-methyl-2-(pyridin-2-yl)-1 H -imidazole ( L OH,OH ) as the first example of ESIPT-capable imidazole derivatives wherein the imidazole moiety simultaneously acts as a proton acceptor and a proton donor. The reaction of L OH,OH with chloroacetone leads to the selective reduction of the imidazolic OH group (whereas the phenolic OH group remains unaffected) and to the isolation of 4-(2-hydroxyphenyl)-5-methyl-2-(pyridin-2-yl)-1 H -imidazole ( L H,OH ), a monohydroxy congener of L OH,OH . Both L OH,OH and L H,OH demonstrate luminescence in the solid state. The number of OH···N proton transfer sites in these compounds (one for L H,OH and two for L OH,OH ) strongly affects the luminescence mechanism and color of the emission: L H,OH emits in the light green region, whereas L OH,OH luminesces in the orange region. According to joint experimental and theoretical studies, the main emission pathway of both compounds is associated with T 1 → S 0 phosphorescence and not related to ESIPT. At the same time, L OH,OH also exhibits S 1 → S 0 fluorescence associated with ESIPT with one proton transferred from the hydroxyimidazole moiety to the pyridine moiety, which is not possible for L H,OH due to the absence of the hydroxy group in the imidazole moiety.

Herein, we report the direct selective C-H lactonization of fatty acids (C5-C16), catalyzed by manganese(II) complexes bearing bis-amino-bis-pyridine ligands. The catalyst system uses the environmentally benign hydrogen peroxide as oxidant and exhibits high efficiency (100-200 TON), providing under optimized conditions γ-lactones in 60-90% yields. Remarkably, by changing the reaction conditions, the oxidation of hexanoic acid can be diverted toward formation of δ-caprolactone in up to 67% yield. Furthermore, the possibility of obtaining (ω-1)-hydroxy derivatives from linear C7-C10 acids in up to 48% yields has been demonstrated.

Porous metal-organic framework [Zn 2 (ttdc) 2 (bpy)] ( 1 ) based on thieno [3,2-b]thiophenedicarboxylate (ttdc) was synthesized and characterized. The structure contains intersected zig-zag channels with an average aperture of 4 × 6 Å and a 49% ( v/v ) guest-accessible pore volume. Gas adsorption studies confirmed the microporous nature of 1 with a specific surface area (BET model) of 952 m 2 ·g -1 and a pore volume of 0.37 cm 3 ·g -1 . Extensive CO 2 , N 2 , O 2 , CO, CH 4 , C 2 H 2 , C 2 H 4 and C 2 H 6 gas adsorption experiments at 273 K and 298 K were carried out, which revealed the great adsorption selectivity of C 2 H 6 over CH 4 (IAST selectivity factor 14.8 at 298 K). The sulfur-rich ligands and double framework interpenetration in 1 result in a dense decoration of the inner surface by thiophene heterocyclic moieties, which are known to be effective secondary adsorption sites for carbon dioxide. As a result, remarkable CO 2 adsorption selectivities were obtained for CO 2 /CH 4 (11.7) and CO 2 /N 2 (27.2 for CO 2 :N 2 = 1:1, 56.4 for CO 2 :N 2 = 15:85 gas mixtures). The computational DFT calculations revealed the decisive role of the sulfur-containing heterocycle moieties in the adsorption of CO 2 and C 2 H 6 . High CO 2 adsorption selectivity values and a relatively low isosteric heat of CO 2 adsorption (31.4 kJ·mol -1 ) make the porous material 1 a promising candidate for practical separation of biogas as well as for CO 2 sequestration from flue gas or natural gas.

We report here a series of original ligand-supported trigonal planar Au@Ag 3 clusters exhibiting bright solid-state phosphorescence in violet to deep-blue range (λ max =410-442 nm) with remarkably short decay times (0.36-1.36 μs) and up to 96 % emission quantum yield at 298 K., (© 2022 Wiley-VCH GmbH.)

We report herein a family of polynuclear complexes, [Au@Ag 4 (Py 3 P) 4 ]X 5 and [Au@Cu 4 (Py 3 P) 4 ]X 5 [X = NO 3 , ClO 4 , OTf, BF 4 , SbF 6 ], containing unprecedented Au-centered Ag 4 and Cu 4 tetrahedral cores supported by tris(2-pyridyl)phosphine (Py 3 P) ligands. The [Au@Ag 4 ] 5+ clusters are synthesized via controlled substitution of the central Ag(I) ion in all-silver [Ag@Ag 4 ] 5+ precursors by the reaction with Au( tht )Cl, while the [Au@Cu 4 ] 5+ cluster is assembled through the treatment of a pre-organized [Au(Py 3 P) 4 ] + metallo-ligand with 4 equiv of a Cu(I) source. The structure of the Au@M 4 clusters has been experimentally and theoretically investigated to reveal very weak intermolecular Au-M metallophilic interactions. At ambient temperature, the designed compounds emit a modest turquoise-to-yellow luminescence with microsecond lifetimes. Based on the temperature-dependent photophysical experiments and DFT/TD-DFT computations, the emission observed has been assigned to an MLCT or LLCT type depending on composition of the cluster core.

Inorganic-organic hybrid luminescent materials have received great attention for their potential applications in a wide range of clean/renewable energy-related areas, including photovoltaics and solid-state lighting. Herein, we present a unique and general "Mn + Cu" approach by blending two earth-abundant luminogenic metals, manganese and copper, within a single ionic structure to construct a remarkable family of low-cost and multifunctional hybrid materials featuring dual emission, as well as triboluminescence and second-harmonic generation response. The novel hybrid materials are made of diphosphine dioxide-chelated [Mn(O∧O) 3 ] 2+ cations and various anionic [Cu x I y ] ( y - x )- clusters, ensuring manifestation of dual phosphorescence streamed from octahedral Mn 2+ ions (605-648 nm) and iodocuprate anions (480-728 nm). Noteworthily, the relative ratio of the emission bands, and hence a resulting emission chromaticity, can be tuned in a wide range through modification of cluster [Cu x I y ] ( y - x )- modules. The structural diversity, enhanced robustness, and up to 100% luminescence quantum yield make the designed materials promising phosphors for lighting and sensing applications.

The reactions of CuX 2 (X = Cl, Br) with dipinodiazafluorenes yielded four new complexes [CuX 2 L 1 ] 2 (X = Cl ( 1 ), Br ( 2 ), L 1 = (1R,3R,8R,10R)-2,2,9,9-Tetramethyl-3,4,7,8,9,10-hexahydro-1H-1,3:8,10-dimethanocyclopenta [1,2-b:5,4-b']diquinolin-12(2H)-one) and [(CuX 2 ) 2 L 2 ]n (X = Cl ( 3 ), Br ( 4 ), L 2 = (1R,3R,8R,10R,1'R,3'R,8'R,10'R)-2,2,2',2',9,9,9',9'-Octamethyl-1,1',2,2',3,3',4,4',7,7',8,8',9,9',10,10'-hexadecahydro-1,3:1',3':8,10:8',10'-tetramethano-12,12'-bi(cyclopenta [1,2-b:5,4-b']diquinolinylidene). The complexes were characterized by IR and EPR spectroscopy, HR-ESI-MS and elemental analysis. The crystal structures of compounds 1 , 2 and 4 were determined by X-ray diffraction (XRD) analysis. Complexes 1 - 2 have a monomeric structure, while complex 4 has a polymeric structure due to additional coordinating N,N sites in L 2 . All complexes contain a binuclear fragment {Cu 2 (μ-X) 2×2 } (X = Cl, Br) in their structures. Each copper atom has a distorted square-pyramidal coordination environment formed by two nitrogen atoms and three halogen atoms. The Cu-N ax distance is elongated compared to Cu-N eq . The EPR spectra of compounds 1 - 4 in CH 3 CN confirm their paramagnetic nature due to the d 9 electronic configuration of the copper(II) ion. The magnetic properties of all compounds were studied by the method of static magnetic susceptibility. For complexes 1 and 2 , the effective magnetic moments are µ eff ≈ 1.87 and 1.83 µ B (per each Cu 2+ ion), respectively, in the temperature range 50-300 K, which are close to the theoretical spin value (1.73 µ B ). Ferromagnetic exchange interactions between Cu(II) ions inside {Cu 2 (μ-X) 2 X 2 } (X = Cl, Br) dimers ( J / k B ≈ 25 and 31 K for 1 and 2 , respectively) or between dimers ( θ ' ≈ 0.30 and 0.47 K for 1 and 2 , respectively) were found at low temperatures. For compounds 3 and 4 , the magnetic susceptibility is well described by the Curie-Weiss law in the temperature range 1.77-300 K with µ eff ≈ 1.72 and 1.70 µ B for 3 and 4 , respectively, and weak antiferromagnetic interactions (θ ≈ -0.4 K for 3 and -0.65 K for 4 ). Complexes 1 - 4 exhibit high catalytic activity in the oxidation of alkanes and alcohols with peroxides. The maximum yield of cyclohexane oxidation products reached 50% (complex 3 ). Based on the data on the study of regio- and bond-selectivity, it was concluded that hydroxyl radicals play a decisive role in the oxidation reaction. The initial products in reactions with alkanes are alkyl hydroperoxides.

A series of heteroleptic square-planar Pt and Pd complexes with bis(diisopropylphenyl) iminoacenaphtene (dpp-Bian) and Cl, 1,3-dithia-2-thione-4,5-dithiolate (dmit), or 1,3-dithia-2-thione-4,5-diselenolate (dsit) ligands have been prepared and characterized by spectroscopic techniques, elemental analysis, X-ray diffraction analysis, and cyclic voltammetry (CV). The intermolecular noncovalent interactions in the crystal structures were assessed by density functional theory (DFT) calculations. The anticancer activity of Pd complexes in breast cancer cell lines was limited by their solubility. Pd(dpp-Bian) complexes with dmit and dsit ligands as well as an uncoordinated dpp-Bian ligand were devoid of cytotoxicity, while the [Pd(dpp-Bian)Cl 2 ] complex was cytotoxic. On the contrary, all Pt(dpp-Bian) complexes demonstrated anticancer activity in a low micromolar concentration range, which was 8-20 times higher than the activity of cisplatin, and up to 2.5-fold selectivity toward cancer cells over healthy fibroblasts. The presence of a redox-active dpp-Bian ligand in Pt and Pd complexes resulted in the induction of reactive oxygen species (ROS) in cancer cells. In addition, these complexes were able to intercalate into DNA, indicating the dual mechanism of action.