一种基于偶氮水杨醛酰腙的CN-探针

设计合成了一种基于偶氮苯基团的简单而高效的比色探针L1,并利用紫外-可见吸收光谱考察其对阴离子（F^-, Cl^-, Br^-, I^-, AcO^-, H₂PO₄^-, HSO₄^-, ClO₄^-和CN^-）的识别性能。结果表明：探针L1在DMSO/H₂O（5：5, V/V）的含水体系中,可以实现对CN^-单一选择性识别;且加入CN^-时,溶液颜色立刻由无色变为红色,而加入其它阴离子则无变化,说明该探针能够实现对CN^-的裸眼识别。另外,该探针对CN^-的检测灵敏度较高,最低检测限达到了1.3 μmol·L^-1。此外,我们制作了负载有探针分子L1的试纸条,能够更加方便快捷的检测CN^-。     

Coordination polymer chains built from CuII and adipate ions linked by hydrogen bonds to form a three‐dimensional framework structure

In the title compound, catena‐poly[bis[(2,2′‐bipyridine‐κ²N,N′)(1,1,3,3‐tetracyano‐2‐ethoxypropenido‐κN)copper(II)]‐μ₄‐hexanedioato‐κ⁶O¹,O^1′:O¹:O⁶,O^6′:O⁶], [Cu₂(C₉H₅N₄O)₂(C₆H₈O₄)(C₁₀H₈N₂)₂]_n, the adipate (hexanedioate) dianion lies across a centre of inversion in the space group P. The Cu^II centre adopts a distorted form of axially elongated (4+2) coordination, and the Cu^II and adipate components form a one‐dimensional coordination polymer from which the 2,2′‐bipyridine and 1,1,3,3‐tetracyano‐2‐ethoxypropenide components are pendent, and where each adipate dianion is bonded to four different Cu^II centres. The coordination polymer chains are linked into a three‐dimensional framework structure by a combination of C—H...N and C—H...O hydrogen bonds, augmented by a π–π stacking interaction.     

Exploring the Reactivity of B-Connected Carboranylphosphines in Frustrated Lewis Pair Chemistry: A New Frame for a Classic System

The primary phosphines MesPH₂ and tBuPH₂ react with 9-iodo-m-carborane yielding B9-connected secondary carboranylphosphines 1,7-H₂C₂B₁₀H₉-9-PHR (R=2,4,6-Me₃C₆H₂ (Mes; 1 a ), tBu ( 1 b )). Addition of tris(pentafluorophenyl)borane (BCF) to 1 a , b resulted in the zwitterionic compounds 1,7-H₂C₂B₁₀H₉-9-PHR(p-C₆F₄)BF(C₆F₅)₂ ( 2 a , b ) through nucleophilic para substitution of a C₆F₅ ring followed by fluoride transfer to boron. Further reaction with Me₂SiHCl prompted a H−F exchange yielding the zwitterionic compounds 1,7-H₂C₂B₁₀H₉-9-PHR(p-C₆F₄)BH(C₆F₅)₂ ( 3 a , b ). The reaction of 2 a , b with one equivalent of R'MgBr (R’=Me, Ph) gave the extremely water-sensitive frustrated Lewis pairs 1,7-H₂C₂B₁₀H₉-9-PR(p-C₆F₄)B(C₆F₅)₂ ( 4 a , b ). Hydrolysis of the B−C₆F₄ bond in 4 a , b gave the first tertiary B-carboranyl phosphines with three distinct substituents, 1,7-H₂C₂B₁₀H₉-9-PR(p-C₆F₄H) ( 5 a , b ). Deprotonation of the zwitterionic compounds 2 a , b and 3 a , b formed anionic phosphines [1,7-H₂C₂B₁₀H₉-9-PR(p-C₆F₄)BX(C₆F₅)₂]⁻[DMSOH]⁺ (R=Mes, X=F ( 6 a ), R=tBu, X=F ( 6 b ); R=Mes, X=H ( 7 a ), R=tBu, X=H ( 7 b )). Reaction of 2 a , b with an excess of Grignard reagents resulted in the addition of R’ at the boron atom yielding the anions [1,7-H₂C₂B₁₀H₉-9-PR(p-C₆F₄)BR’(C₆F₅)₂]⁻ (R=Mes, R’=Me ( 8 a ), R=tBu, R’=Me ( 8 b ); R=Mes, R’=Ph ( 9 a ), R=tBu, R’=Ph ( 9 b )) with [MgBr(Et₂O)_n]⁺ as counterion. The ability of the zwitterionic compounds 3 a , b to hydrogenate imines as well as the Brønsted acidity of 3 a were investigated.     

[2+3] Amide Cages by Oxidation of [2+3] Imine Cages – Revisiting Molecular Hosts for Highly Efficient Nitrate Binding

The pollution of groundwater with nitrate is a serious issue because nitrate can cause several diseases such as methemoglobinemia or cancer. Therefore, selective removal of nitrate by efficient binding to supramolecular hosts is highly desired. Here we describe how to make [2+3] amide cages in very high to quantitative yields by applying an optimized Pinnick oxidation protocol for the conversion of corresponding imine cages. By NMR titration experiments of the eight different [2+3] amide cages with nitrate, chloride and hydrogen sulfate we identified one cage with an unprecedented high selectivity towards nitrate binding vs. chloride (S=705) or hydrogensulfate (S>13500) in CD₂Cl₂/CD₃CN (1 : 3). NMR experiments as well as single-crystal structure comparison of host-guest complexes give insight into structure-property-relationships.     

Simultaneous analysis of six inorganic anions in urine by double-suppress ion-exchange chromatography

This study is aimed to establish a simple, rapid, and accurate ion chromatography approach for the simultaneous detection of six inorganic anions in urine. Various performance parameters affecting the determination of anions were optimized, including the selection of sample protein precipitation agent, eluent, and flow rate. The final eluent was 3.6 mmol/L sodium carbonate and 12% isopropanol with a flow rate of 0.6 mL/min. Acetonitrile was used for pretreatment to precipitate proteins, and the volume ratio of urine to acetonitrile was 1:4. The correlation coefficient of the target anion calibration curve ranged from 0.9973 to 0.9999. The limit of detection ranged from 1.50 to 12.0 μg/L, and the method detection limit ranged from 15.0 to 120 μg/L. The standard recovery rate for low, medium, and high concentrations ranged from 90 to 110%. The inter-day and intra-day relative standard deviations were <5%. The method has high accuracy and good reproducibility and is suitable for the separation and determination of anions in urine.     

Effective biosorption of arsenic from water using La(III) loaded carboxyl functionalized watermelon rind

Arsenic is highly toxic and carcinogenic element that mainly enters into our body through drinking water and caused adverse effect even at low concentration. A new type of cation exchanger is developed from waste biomass of watermelon rind after increasing the carboxyl functional groups by saponification. Saponified Watermelon Rind (SWR) was further loaded with La(III) to attenuate the contamination of As(III) from water. Characterization of biosorbent was performed using Fourier Transform Infra-Red (FTIR) spectroscopy, Field emission Scanning Electron Microscopy (Fe-SEM,) Energy Dispersive X-ray (EDX) spectroscopy and zeta potential analysis. Arsenic speciation of sorption product through X-ray photoelectron spectroscopic (XPS) analysis revealed that As(III) is partially converted into As(V) during biosorption process. The biosorption tests for As(III) were explored under different operating conditions. La(III)-SWR towards As(III) biosorption was best described by Langmuir biosorption isotherm and pseudo second order kinetic model. At a pH of 12.08, the optimum biosorption capacity was found to be 37.73 ± 0.12, 48.78 ± 0.09, 62.50 ± 0.11 mg/g, respectively at temperatures 298 K, 303 K and 308 K. The existance of chloride and nitrate showed negligible interference whereas sulphate and phosphate significantly inhibits As(III) biosorption. Thermodynamic study showed spontaneous and endothermic nature As(III) biosorption onto La(III)-SWR. The sorbed As(III) was eluted almost completely using 2 M NaOH. The findings of this study insinuated that La(III)-SWR biosorbent investigated in this study can be a low cost, environmentally benign and eco-friendly material for the treatment of aqueous solution polluted with arsenic ions.     

A Simple Homoleptic Gallium(I) Olefin Complex: Mimicking Transition‐Metal Chemistry at a Main‐Group Metal?

The earth‐metal olefin complex [Ga ^I (COD)₂]⁺[Al(OR^F)₄]^? (COD=1,5‐cyclooctadiene; R^F=C(CF₃)₃) constitutes the first homoleptic olefin complex of any main‐group metal accessible as a bulk compound. It is straight forward to prepare in good yield and constitutes an olefin complex of a main‐group metal that—similar to many transition‐metals—may adopt the +1 and +3 oxidation states opening potential applications. Crystallographic‐, vibrational‐ and computational investigations give an insight to the atypical bonding between an olefin and a main‐group metal. They are compared to classical transition‐metal relatives.     

Understanding the Chloride Affinity of Barbiturates for Anion Receptor Design

Due to their potential binding sites, barbituric acid (BA) and its derivatives have been used in metal coordination chemistry. Yet their abilities to recognize anions remain unexplored. In this work, we were able to identify four structural features of barbiturates that are responsible for a certain anion affinity. The set of coordination interactions can be finely tuned with covalent decorations at the methylene group. DFT-D computations at the BLYP-D3(BJ)/aug-cc-pVDZ level of theory show that the C−H bond is as effective as the N−H bond to coordinate chloride. An analysis of the electron charge density at the C−H⋅⋅⋅Cl⁻ and N−H⋅⋅⋅Cl⁻ bond critical points elucidates their similarities in covalent character. Our results reveal that the special acidity of the C−H bond shows up when the methylene group moves out of the ring plane and it is mainly governed by the orbital interaction energy. The amide and carboxyl groups are the best choices to coordinate the ion when they act together with the C−H bond. We finally show how can we use this information to rationally improve the recognition capability of a small cage-like complex that is able to coordinate NaCl.     

Zn(ferulate)-LSH Systems as Multifunctional Filters

Excessive UV solar radiation exposure causes human health risks; therefore, the study of multifunctional filters is important to skin UV protective ability and also to other beneficial activities to the human organism, such as reduction of reactive oxygen species (ROS) responsible for cellular damages. Potential multifunctional filters were obtained by intercalating of ferulate anions into layered simple metal hydroxides (LSH) through anion exchange and precipitation at constant pH methods. Ultrasound treatment was used in order to investigate the structural changes in LSH-ferulate materials. Structural and spectroscopic analyses show the formation of layered materials composed by a mixture of LSH intercalated with ferulate anions, where carboxylate groups of ferulate species interact with LSH layers. UV-VIS absorption spectra and in vitro SPF measurements indicate that LSH-ferulate systems have UV shielding capacity, mainly UVB protection. The results of reactive species assays show the ability of layered compounds in capture DPPH^•, ABTS^•+, ROO^•, and HOCl/OCl⁻ reactive species. LSH-ferulate materials exhibit antioxidant activity and singular optical properties that enable their use as multifunctional filters.     

Synthesis and Ambiphilic Reactivity of Metalated Diorgano-Phosphonite Boranes

Unprecedented metalated phosphonite boranes were prepared from PH-substituted precursors and silyl amides. Although potassium derivatives were thermally stable and could even be isolated and structurally characterised, lithiated analogues proved to be unstable towards self-condensation under cleavage of LiOR at ambient temperature. Reaction studies revealed that the metalated phosphonite boranes exhibit ambiphilic character. Their synthetic potential as nucleophilic building blocks was demonstrated in the synthesis of the first stannylated phosphonite representing a new structural motif in phosphine chemistry.