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Three bis-benzimidazolyl bidentate ligands with phenolyl ether linkers, 1,n-bis[2-(1H-1,3-benzimidazol-1-ylmethyl)phenoxy]alkane (L1: n = 1, L2: n = 3, L3: n = 4), and their six metal complexes were synthesized by the reactions of the respective ligands with metal salts. The six metal complexes included two cobalt(II) complexes ([Co(L1)(NO3)2] (1) and [Co(L3)(LA)]n (6) (LA = maleate)), two copper(II) complexes ([Cu(L1)(SO4)]2 (4) and [Cu(L3)(SO4)]2 (5)), one zinc(II) complex ([Zn(L1)(NO3)2] (2)) and one nickel(II) complex ([Ni(L2)(NO3)2] (3)). Complexes 1 and 2 had one 16-membered macrometallocycle, and complex 3 had one 18-membered macrometallocycle. In complexes 4 and 5, two SO42- joined two macrometallocycles together (16-membered macrometallocycle for 4 and 19-membered macrometallocycle for 5). In complexes 1-5, each macrometallocycle was constructed from one ligand and one metal ion. In complex 6, 19-membered macrometallocycles were connected together by maleate groups (LA) to form a 1D polymeric chain, where each 19-membered macrometallocycle was constructed from one L3 and one Co(II) ion. In crystal packings of complexes 1-6, H-bonds, π--π interactions and C--H•••π contacts participated in the formation of 2D supramolecular layers and 3D supramolecular architectures. The conformations of complexes 1-6 were also analyzed. Additionally, the recognition performance of complex 1 as a chemosensor for HSO4- was studied through fluorescence spectra, UV/vis spectra, 1H NMR titrations, HRMS spectra and IR spectra. The large binding constant (1.81 x 104 M-1) showed that there was a strong acting force between 1 and HSO4-, and the low detection limit (1.40 x 10-7 mol L-1) indicated that the detection of 1 for HSO4- was sensitive. The experimental results showed that complex 1 can effectively differentiate HSO4- from other anions. [ABSTRACT FROM AUTHOR]

Torrefaction is an effective method to improve the quality of biomass feedstocks for a subsequent thermal conversion process. Torrefaction has been widely developed for biomass upgrading in terms of increasing bulk and energy densities, reducing water and oxygen contents, and improving hydrophobic properties, which are favorable for transportation and storage. Moreover, the torrefied biomass can be easily ground to even particle sizes, which favor the downstream thermochemical conversion process such as gasification. This paper reports on the progress in the dry and wet torrefaction of biomass sources. Key findings and challenges of torrefied biomass gasification are highlighted as well. In general, the properties of biomass feedstocks can be improved by the torrefaction process. Torrefaction for biomass gasification can improve the quality of syngas. In particular, gasification of torrefied biomass involves a merit of volatile matter (tar precursor) removal prior to the gasification process. The properties of torrefied biomass are significantly affected by the torrefaction conditions mainly including atmosphere, temperature, and pressure. The presence of an appropriate amount of oxygen gas leads to a superior performance for biomass torrefaction. The oxygen-containing gas and the waste heat from industrial flue gas can be utilized to reduce the operating cost, thus making the biomass torrefaction pretreatment more commercially feasible. [ABSTRACT FROM AUTHOR]

Pretreatment facilitates cost-effective operations on lignocellulosic biomass ranging from densification to deconstruction and bioproduct development. However, determining molecular-level mechanisms behind pretreatment and their effects has remained elusive. Here, we combine computational simulation and experiment to investigate the effects on wheat straw agricultural residue densification of an emerging pretreatment solvent, namely, a deep eutectic solvent (DES) consisting of choline chloride (ChCl) and oxalic acid (OA). Ab initio molecular dynamics indicates that dissociation of lignin from cellulose in lignin–carbohydrate complexes, which does not occur to a significant extent in aqueous solution, is favorable in the DES and occurs via cleavage of the guaiacyl : xylose ether bond linkage by OA. The ensuing hemicellulose removal exposes lignin to the DES which, molecular dynamics simulation indicates, leads to lignin expansion. The resulting changes in wheat straw fiber structure, lignin distribution, and functional group modifications upon DES treatment by scanning electron and fluorescence microscopy along with Fourier-transform infrared spectroscopy. The molecular expansion of lignin enhances inter-particle binding in wheat straw, leading to denser structures under pelletization. The resulting high mechanical stability and combustion properties make the wheat straw a suitable precursor of high-quality densified solids (e.g., solid biofuel). Overall, we shed light on the molecular-level mechanisms involved in DES pretreatment for biomass densification, demonstrated here in the development of a solid biofuel. The approach here illuminates the rational design from first chemical principles of methods to convert lignocellulosic resources into advanced materials. [ABSTRACT FROM AUTHOR]

Carbon–phosphorus bond formation is of great importance in synthetic chemistry. A versatile strategy for the formation of carbon–phosphorus bonds involves the addition of phosphorus radicals to π-systems. However, the generation methods of phosphorus radicals are primarily restricted to homolytic cleavage of phosphorus–hydrogen bonds with excess peroxides or toxic metal salts as oxidants. Herein, we introduce a photoinduced palladium-catalyzed generation of phosphorus radicals using inexpensive and readily available Cl–phosphine oxides and Cl–phosphates as the phosphorus radical precursors. The key step for this strategy lies in the reductive activation of phosphorus–chloride bonds with the excited palladium complex under visible light irradiation. The involvement of phosphorus radicals has been evidenced by EPR spectroscopy and radical trapping experiments. Based on this strategy, both phosphinyl and phosphonyl groups could be regiospecifically incorporated into simple alkenes and heteroaromatic compounds via radical mediated carbon–phosphorus bond formation. Besides, carbon–phosphorus difunctionalization of alkenes was also achieved to afford phosphorylated oxindoles. [ABSTRACT FROM AUTHOR]

Due to their hazard to biological systems, it is urgent to develop materials that can rapidly and sensitively detect the concentration of H2PO4− and OCN− ions. In this work, a new CdII-based luminescent metal–organic framework with the formula [Cd(BTDB)(2,6-BBIP)]n (JXUST-47, H2BTDB = (benzo[c][1,2,5]thiadiazole-4,7-diyl)dibenzoic acid, 2,6-BBIP = 2,6-bis(benzimidazol-1-yl)pyridine) and sql topology was successfully synthesized using a mixed-ligand strategy. JXUST-47 shows good chemical and thermal stability. It also exhibits weak quenching and fluorescence blue shift for H2PO4− and red shift for OCN−, with the detection limits of 0.106 and 0.128 mM, respectively. In addition, considering the demand for H2PO4− and OCN− ion detection, by combining this with the functions of a smartphone, the chroma of photographs have been used to realize the consecutive visual detection of the concentration of these ions. [ABSTRACT FROM AUTHOR]

Controlled self-assembly of predetermined multi-nuclear lanthanide organic polyhedra (LOPs) still presents a challenge, primarily due to the unpredictable coordination numbers and labile coordination geometries of lanthanide ions. In this study, through introducing triazole-based chelates to increase the chelating angle of C2-symmetric linear ligands and stabilize the coordination geometry of Eu(III) centers, M4L6-type (M = EuIII, L = ligand) tetrahedra were efficiently synthesized, especially a biphenyl-bridged ligand which is well known to form M2L3-type helicates. A series of LOPs were formed and characterized by high-resolution electrospray ionization time-of-flight mass spectroscopy (ESI-TOF-MS) and X-ray crystallography. Moreover, the europium complexes exhibit bright emission (luminescence quantum yield up to 42.4%) and circularly polarized luminescence properties (‖glum‖ up to 4.5 × 10−2). This study provides a feasible strategy for constructing multi-nuclear luminescent LOPs towards potential applications. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are novel inorganic–organic hybridized crystals with a wide range of applications. In the last twenty years, fluorescence sensing based on MOFs has attracted much attention. MOFs can exhibit luminescence from metal nodes, ligands or introduced guests, which provides an excellent fluorescence response in sensing. However, single-signal emitting MOFs are susceptible to interference from concentration, environment, and excitation intensity, resulting in poor accuracy. To overcome the shortcomings, dual-emission MOF-based ratiometric fluorescence sensors have been proposed and rapidly developed. In this review, we first introduce the luminescence mechanisms, synthetic methods, and detection mechanisms of dual-emission MOFs, highlight the strategies for constructing ratiometric fluorescence sensors based on dual-emission MOFs, and classify them into three categories: intrinsic dual-emission and single-emission MOFs with luminescent guests, and non-emission MOFs with other luminescent materials. Then, we summarize the recent advances in dual-emission MOF-based ratiometric fluorescence sensors in various analytical industries. Finally, we discuss the current challenges and prospects for the future development of these sensors. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are a novel class of hybrid porous multi-functional materials consisting of metal ions/clusters and organic ligands. MOFs have exclusive benefits due to their tunable structure and diverse properties. Luminescent MOFs (LMOFs) exhibit both porosity and light emission. They display abundant host and guest responses, making them conducive to sensing. Currently, LMOF sensing research is gaining more depth, with attention given to their device and practical applications. This work reviews recent advancements and device applications of LMOFs as chemical sensors toward ions, volatile organic compounds, biomolecules, and environmental toxins. Furthermore, the detection mechanism and the correlation between material properties and structure are elaborated. This analysis serves as a valuable reference for the preparation and efficient application of targeted LMOFs. [ABSTRACT FROM AUTHOR]

Ratiometric luminescent temperature sensing based on a single matrix is highly desirable at present. However, the adjustments of the temperature response range and sensitivity are still a huge challenge. Herein, a novel series of isostructural three-dimensional (3D) lanthanide metal–organic frameworks (Ln-MOFs) {[Ln4(ebdc)6(DMF)2.75(H2O)7]}n (HPU-99, where Ln = Eu and EuxTb1−x, H2ebdc = 5-ethynyl-isophthalic acid) are synthesized by a solvothermal method using a 5-ethynyl-isophthalic acid ligand (H2ebdc). Notably, a series of Ln-MOFs EuxTb1−x-HPU-99 (x = 0.05, 0.1, 0.2) are obtained by adjusting the proportion of Eu3+/Tb3+ in the bimetallic materials, which exhibit temperature dependent luminescent behavior with a fluorescence color gradient and demonstrate that chemical components would affect the ratiometric luminescent temperature sensing performance. Furthermore, the luminescence of HPU-99 is altered after the argentophilic alkynyl groups anchor the silver nanoclusters (Ag NCs). This work showcases that bimetallic Ln-MOFs have great potential in luminescent sensing at an atomically precise level. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are a unique class of multifunctional hybrid crystals that have been successfully utilized in diverse ranges of applications. However, since MOFs are prone to aqueous degradation, the development of stable luminescent MOF platforms in aqueous media is still a huge challenge. Here, a novel dual-ligand Eu3+/DUT-52-COOH composite is prepared based on the luminescent DUT-52 prototype structure via a dual-ligand strategy and a post-synthetic modification (PSM) method. The functionalized Eu3+/DUT-52-COOH material exhibits dual emission and good photothermal stability in aqueous media. Thus, Eu3+/DUT-52-COOH is developed as a ratiometric luminescent sensor to achieve highly selective and sensitive detection of Cu2+ and Cr2O72− in aqueous solutions and has a low detection limit of 3.43 μM and 25.7 nM, respectively. This work is one of the few cases of detecting Cu2+ and Cr2O72− in aqueous media based on a DUT-52, and the detection signals can be observed by the bare eye without using sophisticated analytical instruments. The possible sensing mechanism is discussed in detail. The results obtained in this project may provide broad prospects for developing smart sensing systems to accomplish highly efficient, easily operable and quantitative intelligent recognition of Cu2+ and Cr2O72−. [ABSTRACT FROM AUTHOR]

Catalytic CO2 methanation is of particular significance and growing interest due to its applications in many important industrial fields. The development of advanced heterogeneous catalysts for CO2 methanation depends predominantly on the rational regulation of metal–support interaction (MSI), which remains challenging despite recent progress. Here, we develop a new heterogeneous catalyst, TiH2-supported Ru nanoparticles (NPs), which features notable electron transfer from the TiH2 support to Ru NPs and enhanced capability of CO intermediate activation for CO2 methanation, distinct from TiO2-supported Ru catalysts synthesized under similar mild conditions. The electron transfer behavior and hydrogen spillover effect in TiH2-supported Ru NPs (denoted as mRTH, where m refers to the mass loading of the RuCl3 precursor in mg) are optimized at a moderate Ru loading level of 9.8 wt% in 100RTH, where the impacts of Ru loading on CO intermediate activation, H2 activation and catalyst surface hydration are synergistically balanced. When evaluated at 200 °C under 4 bar pressure, 100RTH delivers a notable CH4 selectivity of 99.8% and a superior CH4 production rate of 168.7 mmol h−1 gRu−1, which is 21.1 times more active than pure Ru NPs. Our work provides valuable insights into the MSI-directed development of heterogeneous catalysts for highly efficient CO2 conversion and utilization. [ABSTRACT FROM AUTHOR]

Developing high-accuracy luminescent sensors for detecting emerging environmental pollutants is of great importance and is still a challenge. Utilizing a 4-carboxyphenylphosphonic acid (H3pbc) ligand, a novel one-dimensional (1D) Zn-based coordination polymer with the formula [Zn2(Hpbc)2(2,2′-bipy)(H2O)]·H2O (Zn–CP, H3pbc = 4-HOOCC6H4PO3H2, 2,2′-bipy = 2,2′-bipyridine) has been hydrothermally synthesized. Each of the 1D chains was linked via π–π stacking interactions and formed a supramolecular framework. Furthermore, due to the existence of uncoordinated –COOH groups, the terbium-functionalized hybrid (Tb3+@Zn-CP) was prepared by introducing Tb3+ ions into the structure through coordinated postsynthetic modification (PSM). Tb3+@Zn-CP shows the characteristic emission of Tb3+ ions due to the "antenna effect" of the H3pbc ligand. Based on the excellent luminescence properties and structural stabilities of Zn-CP and Tb3+@Zn-CP, they can be used as highly sensitive and selective luminescent probes of the UV filter BP (benzophenone) depending on multiquenching effects. In addition, their obvious color change can be easily distinguished by the naked eye under ultraviolet light, which was successfully used in the preparation of portable BP test paper. More importantly, Tb3+@Zn-CP is the first example of CPs as a ratiometric luminescent sensor for BP. This work provides a novel strategy for the construction of ratiometric luminescent probes of BP-type UVFs through coordinated postsynthetic modification. [ABSTRACT FROM AUTHOR]

In this work, a novel composite material (HPU-24@Ru) has been prepared by combining a blue-emission Cd-based metal-organic framework (MOF, [Cd2(TCPE)(DMF)(H2O)3]n, HPU-24) with a red-emission tris (2,2′-bipyridine) dichlororuthenium(II) hexahydrate ([Ru(bpy)3]2+) molecule for ratiometric fluorescence sensing of Al3+ ions in aqueous medium and high-level dynamic anticounterfeiting application. The luminescence measurement results indicated that the fluorescence intensity of HPU-24 at 446 nm showed a red shift in the presence of Al3+ ions, and the new peak appeared at 480 nm and continued to increase with an increase in Al3+ ion concentration. Meanwhile, the fluorescence intensity of [Ru(bpy)3]2+ almost showed no change. The detection limit was calculated as 11.63 μM, which was better than that for the MOF-based Al3+ ions in some reported examples in aqueous media and achieved through strong electrostatic interactions between HPU-24@Ru and Al3+ ions. Moreover, owing to the particularity of the tetrastyryl structure in HPU-24, HPU-24@Ru showed intriguing temperature-dependent emission behavior. This unique structure provides the composite material HPU-24@Ru with attributes for high-level information encryption that make it difficult for counterfeiters to identify all of the right decryption measures. [ABSTRACT FROM AUTHOR]

We designed and synthesized a semi-rigid bis-tridentate ligand L which could undergo a trans-to-cis conformational transition when coordinated onto lanthanum ions through the rotation of the single bond on the central terphenyl bridge. By adjusting the metal/ligand ratio, a single-ligand bridged dinuclear complex La2L3 and an infinitely extending two-dimensional layered metal organic polymer (La2L2)n can be obtained. Through the induction of the chiral auxiliary ligand G R/S , these two achiral assemblies could both be transformed into the chiral mononuclear three-component complex LaLG R/S . In addition, we also realized a linear ee sensing for the auxiliary ligand by induced circular dichroism. [ABSTRACT FROM AUTHOR]

The metal–organic framework UiO-66 with metal zirconium as the node has been synthesized using zirconium chloride and terephthalic acid. Anticancer drugs (CPT and DOX) and a photosensitizer (RB) were encapsulated via a post-loading method, and then the surface was modified with NH2-PEG-FA to form RB-Drug@UiO-66-FA. The introduction of folic acid (FA) increased the stability and biocompatibility of the nanomaterials. Through X-ray diffraction and zeta potential analysis, we confirm that the modified material maintains its original structure and can effectively encapsulate the drug. By testing its performance, we showed that the drugs were released at high levels in the acidic environment where cancer cells survive. After 552 nm laser irradiation, a large amount of 1O2 was produced, promoting apoptosis. These results indicated that the materials demonstrate a good, combined effect of chemotherapy and photodynamic therapy. [ABSTRACT FROM AUTHOR]

It is necessary to decrease the application cost of luminescent Ln-MOF sensors to develop multiple functionalities. The ingenious design of ligands and the rational doping of Ln3+ ions are the main approaches to endowing Ln-MOFs with more functionalities. "V" shaped ligands can cause diamond pore channels commonly. "O＝C–NH" groups as hydrogen bonding sites not only can participate in supramolecular self-assembly but also can achieve molecular recognition. Based on the above considerations, a "V" shaped ligand, H2L, with a suitable triplet state and "O＝C–NH" groups was designed and synthesized firstly. And the Ln-MOFs (Ln = Eu, Gd, Tb) were obtained by solvothermal reactions. Single crystal X-ray diffraction showed that Ln-MOFs had two types of diamond pore channels where "O＝C–NH" groups adhered to the surface. "O＝C–NH" groups not only played an important role in the stacking process of 2D coordinated layers but also can reduce the non-radiative transition resulting from molecular vibration. The Eu-MOF and Tb-MOF not only can emit strong "f–f" transitions characteristic of luminescence but also can detect o-phenylenediamine (OPD) and p-phenylenediamine (PPD) by luminescence quenching. Besides, EuxTb1−x-MOFs (x = 0.02, 0.05, 0.1) were synthesized and can be used as ratio luminescence thermometers whose maximum relative sensitivities were 1.19% K−1 at 400 K. It is pointed out specifically that the relationship between the relative sensitivities and the Eu3+ content was studied. What's more, our work not only developed a series of Ln-MOF luminescent sensors by designing functional ligands and doping Ln3+ rationally but also provided valuable knowledge for the following work. [ABSTRACT FROM AUTHOR]

Chiral supramolecular lanthanide-helicates are regarded as promising chiroptical materials due to their combination of ground and excited state chirality and special luminescence properties from Ln3+, named circularly polarized luminescence (CPL). However, the sophisticated and costly asymmetric syntheses decelerate their research progress. Herein, a chiral induction strategy is employed to break the racemic equilibrium of lanthanide helicate by the formation of a compact ion pair. The synthesized chiral guanidine cation ((R/S)-HG) helps to effectively transfer chirality to anionic quadruple-stranded helicate by electrostatic, H bonds, and multiple C–H⋯F and N–H⋯F interactions. The diastereoselective control was confirmed by X-ray crystallography and CD and CPL spectroscopy, where (S)-HG prefers to bind a P (ΔΔ) helical enantiomer, in contrast a M helicate for (R)-HG. Additionally, the inconsistency of CD and CPL spectra in assessing the perturbation of a racemic equilibrium discloses their complementary advantages on monitoring molecular chirality. In the case of diastereomeric enrichment equilibrium, three pairs of helicates show high luminescence quantum yields of 42%–54%, and large ‖glum‖ with the values of 0.137–0.266. This work provides an effective strategy to synthesize excellent CPL materials based on racemic lanthanide helicate. [ABSTRACT FROM AUTHOR]

Four new ruthenium(II) complexes [Ru(mpt)2(DMSO)2] (1), [Ru(mpt)2(bpy)] (2), [Ru(mpt)2(phen)] (3) and [Ru(mpt)2(tptz)] (4) have been synthesized and characterized by elemental analyses, and IR, 1H and 13C NMR, and electronic absorption spectroscopy. The molecular structures of complexes 1, 2 and 4 were determined crystallographically. The coordination geometries around the ruthenium centre in 1, 2 and 4 are distorted octahedral. As with other Ru(II) pharmacological active compounds, the serum protein binding studies were performed using both the N,S′ and N,N′ donor ligands as well as ruthenium(II) complexes 1–4. It was found that binding of the respective complex was more effective as compared to the respective ligand. Among the different ligands, the order of binding has been evaluated in the order tptz > mpt > phen > Bpy whereas a different order was observed in the respective complexes (4 > 3 > 2 > 1). The binding with tptz and complex 4 was 80% and 84%, respectively. The tptz ligand as well as complex 4 showed hydrophobic interactions which play an important role when interacting with BSA. They possess effective serum protein binding potential within the desired pharmakinetic behavior of good drugs. [ABSTRACT FROM AUTHOR]

Replacing fossil fuels with energy sources and carriers that are sustainable, environmentally benign, and affordable is amongst the most pressing challenges for future socio-economic development. To that goal, hydrogen is presumed to be the most promising energy carrier. Electrocatalytic water splitting, if driven by green electricity, would provide hydrogen with minimal CO2 footprint. The viability of water electrolysis still hinges on the availability of durable earth-abundant electrocatalyst materials and the overall process efficiency. This review spans from the fundamentals of electrocatalytically initiated water splitting to the very latest scientific findings from university and institutional research, also covering specifications and special features of the current industrial processes and those processes currently being tested in large-scale applications. Recently developed strategies are described for the optimisation and discovery of active and durable materials for electrodes that ever-increasingly harness first-principles calculations and machine learning. In addition, a technoeconomic analysis of water electrolysis is included that allows an assessment of the extent to which a large-scale implementation of water splitting can help to combat climate change. This review article is intended to cross-pollinate and strengthen efforts from fundamental understanding to technical implementation and to improve the 'junctions' between the field's physical chemists, materials scientists and engineers, as well as stimulate much-needed exchange among these groups on challenges encountered in the different domains. [ABSTRACT FROM AUTHOR]

Covering: 2000 to mid-2021 The phosphate ester is a versatile, widespread functional group involved in a plethora of biological activities. Its presence in secondary metabolites, however, is relatively rare compared to other functionalities and thus is part of a rather unexplored chemical space. Herein, the chemistry of secondary metabolites containing the phosphate ester group is discussed. The text emphasizes their structural diversity, biological and pharmacological profiles, and synthetic approaches employed in the phosphorylation step during total synthesis campaigns, covering the literature from 2000 to mid-2021. [ABSTRACT FROM AUTHOR]

A new method of ratiometric fluorescence detection of moxifloxacin (MOX) was developed based on carbon quantum dots (CQDs). Through a one-step hydrothermal method using soluble starch and acetic acid buffer solution as precursors, blue fluorescent CQDs with excitation wavelength-dependence were prepared. MOX could combine with CQDs to form a CQDs/MOX through hydrogen bonding. The absorption spectrum of CQDs/MOX and the fluorescence emission spectrum of CQDs overlapped to a certain extent, which allowed for fluorescence resonance energy transfer (FRET) formation between CQDs/MOX and CQDs. For MOX detection, as the MOX concentration increased, the intensity of the fluorescence emission peak of CQDs decreased gradually, the intensity of the fluorescence emission peak of CQDs/MOX increased gradually, and the fluorescence emission peaks of CQDs and CQDs/MOX both had a red-shift. Based on the FRET system between CQDs and CQDs/MOX, a new method for ratiometric fluorescence detection of MOX was established. This method was more effective for MOX detection in the concentration range 3.3 × 10−7 to 2 × 10−6 M. Our method had high sensitivity and selectivity, and the limit of detection was 2.59 nM. The recovery rate of simulated water samples was 98.37–101.15%, which showed that this method was feasible for MOX analysis of actual water samples. [ABSTRACT FROM AUTHOR]

Two dye-loaded metal–organic capsules constructed with different spatial sizes and functional groups simulated the enzymatic substrate activation for hydrogenation of nitroarenes with the kinetics obeying the Michaelis–Menten mechanism. [ABSTRACT FROM AUTHOR]

The control of the self-assembly of lanthanide helical chain and their helical handedness have been investigated for the first time. Δ- and Λ-form lanthanide chain complexes were obtained by introducing thiazolidine ligands that were synthesised from L - and D -cysteine, respectively, and shared the same formula: [Ln2(L)3(H2O)5]∞·3H2O (Ln: Sm and Eu) (L: 2-(2-hydroxy-3,5-dinitrophenyl)thiazolidine-4-carboxylic acid). The crystallographic, circular dichroism, and luminescence properties of these novel lanthanide chain complexes were studied. [ABSTRACT FROM AUTHOR]

A pair of enantiomers {[Cu(L -pro)(L -tyr)]·2H2O}n (L-1) and {[Cu(D -pro)(D -tyr)]·2H2O}n (D-1) based on the chiral ligands L / D -proline and L / D -tyrosine were synthesized and investigated using single-crystal X-ray structure analysis, IR spectroscopy, thermogravimetric analysis, solid-state UV-Vis spectroscopy, circular dichroism, magnetic studies, and DFT calculations. The enantiomers L-1 and D-1 showed left and right-handed helicity, respectively. The magnetic studies indicated that they both showed weak ferromagnetic characteristics. In order to examine the chiroptical activities, we measured the solid-state CD and MCD spectra, which were both of opposite sign for the enantiomers. Compared to the CD spectra, the MCD signals for L-1 and D-1 are intensified at ∼500 nm and weakened at ∼700 nm, which is interesting and needs in-depth research. The further DFT calculations revealed that the magnetic field might directly influence the dyz orbital of the copper and π orbitals of the ligands to increase the electron density and intensify the CD absorption at about 500 nm, impact the dz2 orbital of the copper and π* orbitals of the ligands to decrease the electron density and lower the intensity of CD absorption at around 700 nm, which provides a new threshold for experimentalists and theoreticians to comprehend the magnetism and optics interaction in orbitals. The experimentally and theoretically investigated results are useful for deliberately boosting and weakening the circular dichroism signals in magnetically controlled technologies. [ABSTRACT FROM AUTHOR]

The straightforward synthesis of α-amino phosphine oxides via three-component reactions involving arynes, formamides and diarylphosphine oxides is disclosed. This method employs the aryne to activate formamide, without an external activating reagent, which is operationally simple under mild conditions with high efficiency. Furthermore, mechanistic perception suggests a cascade sequence including formal [2 + 2] cycloaddition of the aryne with a C＝O bond, and a 1,4-addition of the H–P(O) compounds to the enamine intermediates. [ABSTRACT FROM AUTHOR]

In this work, a sustainable one-pot precipitation method was applied for synthesizing strontium phosphate nanoparticles (SrPO NPs), which can be utilized as effective charge separation photocatalysts for the degradation of oncogenic naphthylamine derivatives (congo red). Significant photocatalytic activity of SrPO NPs corresponding to the lowest optical band gap energy of 2.19 eV was calculated by the Tauc plot. The synthesized SrPO NPs belong to the orthorhombic Pnam E crystalline system in which phosphate groups are linked to strontium ions with an average size of 14 nm. The uniform formation of nanoflake-like morphology was analyzed by FE-SEM and HR-TEM techniques. Enhanced photodegradation owing to superior charge separation and interfacial charge transport resistance was confirmed by EIS analysis. The SrPO NPs photocatalyst achieved 98% degradation efficiency under visible light within a short span of time under optimal conditions. The rate constant K = 0.0892 × 10−1 evidently proved that the photodegradation of CR obeys pseudo-first-order reaction kinetics. ROS involved in photodegradation, analyzed by various radical scavengers confirm the involvement of hydroxyl and superoxide radicals during degradation. Finally, the reusability after five consecutive measurements demonstrates that SrPO NPs are excellent and suitable photocatalysts for the detoxification of the anionic azo derivative congo red. [ABSTRACT FROM AUTHOR]