Palladium-anchored calix[4]arene-derived porous organic polymer towards efficient hydrolytic cleavage of carbon disulfide.

The release of carbon disulfide can have adverse effects on our environment and human health. The stability of carbon disulfide and the slow kinetics of hydrolysis can make it challenging to achieve efficient and practical cleavage of the CS bonds. Herein, a calix[4]arene-based porous organic polymer (CPOP-1) is innovatively synthesized through an optimized polycondensation reaction using C-Methylcalix[4]resorcinarene and hexafluoro-hexaazatriphenylene as monomers. Subsequently, palladium-induced calix[4]arene-based porous organic polymer was also synthesized via strong Pd-N coordination bonds to construct the metal-induced porous catalyst (CPOP-2). The polymeric catalyst active center [Pd2+(N^N)(NO3-)2] demonstrated outstanding catalytic hydrolysis performance (11.14 µmol g-1 h-1) in 10.5 h which is significantly enhanced by ca.13.2 times as compared to reported mononuclear Bpy-Pd(NO3)2, and 7.07 times than model trinuclear complex catalyst HATN-Pd-1, respectively. The control experiments revealed that POP catalysts showcased robust stability, prolonged effectiveness, and feasible recyclability during the hydrolytic cleavage of carbon disulfide at room temperature in aqueous solutions. Furthermore, the coordination environment of [Pd2+(N^N)] was validated through XPS, EXAFS, and isotope labeling measurements, and the hydrolysis cleavage products were confirmed e. g. CO2, sulfide, and protons. More importantly, a reaction mechanism was formulated coupled with theoretical calculations, and simulations. The proposed mechanism involves sequential OH- nucleophilic attacks on the carbon atoms of insert-coordinated CS2 and COS, leading to the cleavage of double CS bonds and the formation of CO bonds. The concurrent dissociation of the C-S bond and liberation of CO2 result in an intermediate structure characterized by [(N^N)Pd2+](SH-)2. This intermediate motif serves as the source of the thermodynamic driving force for the reaction.

Self-Assembly of an Anionic [Cu5I8]3- Supramolecular Cluster Driven by Ion-Pair Interaction and Catalytic Properties.

The rational design and controlling synthesis of an anionic cuprous iodide supramolecular cluster with high nuclearity through noncovalent interactions remains a significant challenge. Herein, a cationic organic ligand (L1)3+ was driven by anion-cation ion-pair electrostatic interaction to induce free cuprous iodide to aggregate into an anionic supramolecular cluster, [(Cu5I8)3-(L1)3+] (C1). Moreover, five copper(I) atoms bind with eight iodides through multiply bridged Cu-I bonds associated with intramolecular cuprophilic interactions in this butterfly-shaped cluster core. Supramolecular cluster C1 exhibited a solid-state emission at 380 nm and an emission at 405 nm in acetonitrile at room temperature, respectively. Interestingly, this unprecedented cuprous iodide cluster demonstrated a good catalytic performance for azide-alkyne cycloaddition reaction (CuAAC) and the catalytic yield can be up to 80% for eight different substrates at 80 °C. Furthermore, the density functional theory (DFT) calculation revealed that the thermodynamic-dependent cycloaddition reaction underwent a four-step pathway with an overall energy barrier of -43.6 kcal mol-1 on the basis of intermediates monitored by mass spectrum.

One-step fabrication of all-in-one three-dimensional porous polypyrrole/polydopamine structure for efficient solar vapor generation.

High-quality solar evaporators with all-in-one design are highly desirable for vapor generation, but relevant research is scarce. In this study, a three-dimensional (3D) porous polypyrrole/polydopamine (PPY/PDA) structure was fabricated via a simple heating-assisted rapid oxidative polymerization method. The obtained evaporator has multiple features, and can simultaneously provide rapid water transport channels (average pore sizes âˆ¼ 18.37 nm), low thermal conductivity (0.071 W m-1 K-1), high solar absorbance (97.08%), and good mechanical properties. When it is employed as an evaporator, the calculated water evaporation rate is approximately 2.12 kg m-2h-1, which is comparable to other reported 3D evaporators. Additionally, the evaporator displays great potential for purification toward various nonpotable water, as well as reliable pure water yields in an outdoor application (from 8:00 am to 5:00 pm, the evaporator can produce at least 13.95 L of drinkable water for a 1 m2 sample). We believe that the proposed strategy to fabricate all-in-one evaporators has great significance for scientific research and practical applications.

Anion-Directed Self-Assembly of Calix[4]arene-Based Silver(I) Coordination Polymers and Photocatalytic Degradation of Organic Pollutants.

Coordination polymers (CPs) have recently emerged as promising candidates for heterogeneous photocatalysis due to their structural designability and tunable properties. Herein, we developed two novel Ag(I)-calix[4]arene coordination polymers with the formula {[Ag2(µ-NO3)L1]}n (CP 1) and {[AgL1]·PF6}n (CP 2) (L1 = 2-mercapto-5-methyl-1,3,4-thiadiazole resorcinol calix[4]arene). Crystallography revealed that anion coordination and self-inclusion behavior induced the cavitand and silver ions to self-assemble into well-defined CPs 1 and 2 with different topological coordination frameworks, respectively. Furthermore, CPs 1 and 2 display high photocatalytic activity for the photodegradation of rhodamine B (RhB) and methyl orange (MO) in an aqueous solution under mild conditions (WLED and UV irradiation). The comparison results demonstrate that CP 1 exhibited better photocatalytic performance than CP 2, which correlated well with the differences in their molecular structure and HOMO-LUMO energy gaps. The photocatalysis products and possible intermediates were successfully monitored and determined using mass spectrum, gas chromatography, and electron paramagnetic resonance measurements. The rational photocatalysis mechanism was further investigated and proposed.

Self-Assembly of Mechanoluminochromic Ladder-Shaped Gold(I) Clusters Promoted Using Cooperative Aurophilicity.

The self-assembly of mechanoluminochromic polynuclear gold(I) complexes has attracted more and more attention in the field of supramolecular gold(I) chemistry. In this work, we adopted a stepwise self-assembly strategy to precisely synthesize two polynuclear gold(I) supramolecular clusters. Through cooperative AuI···AuI and Au-N interactions, the gold(I) clusters 1+•BF4- and 24+•4BF4- with Au4 and Au16 cores, respectively, were successfully constructed. In these supramolecular clusters, (dppm)Au2Cl2 coordination motifs and trithiocyanuric linkers were stepwise assembled via sequential thiolate-chloride/phosphine coordination substitution and Au-S/Au-N coordination bond rearrangement. Two well-defined gold(I) supramolecular clusters displayed intense emission both in the solid state and in solution. Furthermore, the ladder-shaped cluster 24+•4BF4- exhibited reversible mechanochromic luminescence behavior in the solid state as well as aggregation-caused redshifted emission in solution. Upon mechanical grinding, the emission of the cluster 24+•4BF4- changed from yellow at 582 nm to red at 612 nm. The initial emission could be fully recovered by treatment with acetonitrile.

Nitrogen and boron co-doped carbon dots as a novel fluorescent probe for fluorogenic sensing of Ce4+ and ratiometric detection of Al3.

Carbon dots have been widely focused on the field of metal ion detection due to their excellent optical property. Herein, novel orange fluorescent nitrogen and boron co-doped carbon dots (NB-CDs) are obtained by one-pot solvothermal using p-phenylenediamine and boric acid as raw materials. The NB-CDs exhibit excitation-independent emissions and the maximum emission wavelength is 597 nm at 420 nm excitation. The fluorescence can be quenched by Ce4+ effectively and selectively, and the detection range of Ce4+ is gained from 0.14 to 180 µM with a detection limit of as low as 0.14 µM. Furthermore, Al3+ can also recombine with NB-CDs surface functional groups, which shows a detection range from 1.07 to 100 µM and a detection limit of as low as 1.07 µM, accompanied with a blue-shift to 527 nm.

One-pot synthesis of double silane-functionalized carbon dots with tunable emission and excellent coating properties for WLEDs application.

Silane-functionalized carbon dots (SiCDs) can be exploited as effective color converting materials for the solid-state light-emitting devices. However, most of SiCDs reported thus far have shown photoluminescence emissions in the blue and green spectral range, which limit them to construct an efficient white light-emitting diodes (WLEDs) due to the lack of long-wavelength emission. Herein, a series of double silane-functionalized carbon dots (DSiCDs) were prepared via a one-step solvothermal method. The results show that the organic functional group of the silane has great influence on the optical properties of DSiCDs and the number of alkoxy group in the silane has great influence on coating properties of DSiCDs. In addition, the DSiCDs prepared by (3-aminopropyl)triethoxysilane and N-[3-(trimethoxysilyl)propyl]ethylenediamine with molar ratio of 7:3 show excellent optical properties with the maximum emission at 608 nm under 570 nm excitation. Furthermore, they can be completely cured within 1 h at room temperature to form fluorescent coating with high stability and strong adhesion to the substrate. Together with their excellent optical and coating properties, they can be directly coated on LED chips to prepare WLEDs, with a CIE coordinate of (0.33,0.31), color rendering index of 81.6, and color temperature of 5774 K.

Topochemical Synthesis of Single-Crystalline Hydrogen-Bonded Cross-Linked Organic Frameworks and Their Guest-Induced Elastic Expansion.

Covalently linked single-crystalline porous organic materials are highly desired for structure-property analysis; however, periodically polymerizing organic entities into high dimensional networks is challenging. Here, we report a series of topologically divergent single-crystalline hydrogen-bonded cross-linked organic frameworks (HCOFs) with visible guest-induced elastic expansions, which mutually integrate high structural order and high flexibility into one framework. These HCOFs are synthesized by photo-cross-linking molecular crystals with alkyldithiols of different chain lengths. Their detailed structural information was revealed by single-crystal X-ray analysis and experimental investigations of HCOFs and their corresponding single-crystalline analogues. Upon guest adsorption, HCOF-2 crystals composed of a 3D self-entangled polymer network undergo anisotropic expansion to more than twice their original size, while the 2D-bilayer HCOF-3 crystals exhibit visible, layered sorption bands and form delaminated sheets along the plane of its 2D layers. The dynamic expansion of HCOF networks creates guest-induced porosity with over 473% greater volume than their permanent voids, as calculated from their record-breaking aqueous iodine adsorption capacities. Temperature-gated DMSO sorption investigations illustrated that the flexible nature of cross-linkers in HCOFs provides positive entropy from the coexistence of multiple conformations to allow for elastic expansion and contraction of the frameworks.

An Elastic Hydrogen-Bonded Cross-Linked Organic Framework for Effective Iodine Capture in Water.

A crystalline microporous hydrogen-bonded cross-linked organic framework has been developed through covalent photo-cross-linking of molecular monomers that are assembled in a crystalline state. The elastic framework expands its void space to adsorb iodine rapidly with a high uptake capacity in an aqueous environment as well as recovering its crystalline form after the release of iodine.

Self-assembly and anion sensing of metal-organic [M6L2] cages from fluorescent triphenylamine tri-pyrazoles with dipalladium(ii,ii) corners.

Three hexametal-organic cages [(N^N)6Pd6L2]6+ with syn, syn, syn conformation were synthesized via the coordination of tris(4-(1H-pyrazol-3-yl)phenyl)amine ligands and [(N^N)2Pd2(NO3)2](NO3)2 dimetallic corners (N^N = 2,2'-bipyridine for 1; 4,4'-dimethylbipyridine for 2; 1,10-phenanthroline for 3). These hexametal-organic cages exhibit anion sensing toward HSO3- in aqueous solution via fluorescent titration and NMR spectroscopy studies.

Programmable self-assembly of water-soluble organo-heterometallic cages [M12M'4L12] using 3-(3,5-dimethyl-1H-pyrazol-4-yl)pentane-2,4-dione (H2L).

A bifunctional ligand H2L featuring primary (pyrazole) and secondary (acetylacetone) coordination sites was preferentially reacted with dimetallic [M2(NO3)2](NO3)2 linkers at the pyrazolyl end of H2L, giving rise to dimetallic corners. Subsequently, the corners serve as the secondary site with M' to form water-soluble organo-heterometallic [M12M'4L12] cages in a stepwise mode.

Hydrolytic cleavage of both CS2 carbon-sulfur bonds by multinuclear Pd(II) complexes at room temperature.

Developing homogeneous catalysts that convert CS2 and COS pollutants into environmentally benign products is important for both fundamental catalytic research and applied environmental science. Here we report a series of air-stable dimeric Pd complexes that mediate the facile hydrolytic cleavage of both CS2 carbon-sulfur bonds at 25 °C to produce CO2 and trimeric Pd complexes. Oxidation of the trimeric complexes with HNO3 regenerates the dimeric starting complexes with the release of SO2 and NO2. Isotopic labelling confirms that the carbon and oxygen atoms of CO2 originate from CS2 and H2O, respectively, and reaction intermediates were observed by gas-phase and electrospray ionization mass spectrometry, as well as by Fourier transform infrared spectroscopy. We also propose a plausible mechanistic scenario based on the experimentally observed intermediates. The mechanism involves intramolecular attack by a nucleophilic Pd-OH moiety on the carbon atom of coordinated µ-OCS2, which on deprotonation cleaves one C-S bond and simultaneously forms a C-O bond. Coupled C-S cleavage and CO2 release to yield [(bpy)3Pd3(µ3-S)2](NO3)2 (bpy, 2,2'-bipyridine) provides the thermodynamic driving force for the reaction.

Self-assembly of a Linear Ni9 Triple-helical Supramolecule with Dominant Ferromagnetic Interactions.

A linear triple-helical supramolecule Ni9 L6 has been prepared through a controllable self-assembly approach using 1,3-bis-(3-oxo-3-phenylpropionyl)-2-hydroxy-5-methylbenzene (H3 L) and Ni(OAc)2 under solvothermal conditions. Single-crystal X-ray diffraction analysis confirms the axial C3 symmetrical helical structure of the product and the temperature-dependent magnetic susceptibility corresponds to a typical shape of a paramagnet showing dominant ferromagnetic exchange couplings between the neighboring Ni(II) ions.

Self-assembly of a Au16 ring via metal-metal bonding interactions.

Metal-metal bonding interactions have been employed as an efficient strategy to generate a number of unique gold(I) metallo-macrocycles with fascinating functions. The self-assembly, crystal structure and emission property of novel nest-like tetramer 1(4), namely, {[Au(4) (µ-dppm)2 (µ-dctp(2-))](BF(4))(2)}(4)⋅(CH(3)CN)(2) (dppm=bis(diphenylphosphino)methane, dctp(2-) =N,N'-bis(dicarbodithioate)-2,11-diaza[3.3]paracyclophane) is reported. The complex has been characterized by single-crystal X-ray diffraction analysis, (1)H NMR spectroscopy, (13)C NMR spectroscopy, and CSI-MS spectrometry. The aggregate demonstrates the sixteen gold(I) atoms are arranged in a ring with a circumference of 50.011(68) Šgenerated by Au(I) ⋅⋅⋅Au(I) attractions. UV/visible and luminescence spectroscopy revealed that this Au(I) ⋅⋅⋅Au(I) bonded metallo-macrocycle exhibited yellow phosphorescence.

Self-assembly of tri-pyrazolate linked cages with di-palladium coordination motifs.

By employing di-palladium complexes [(N^N)2Pd2(NO3(-))2](NO3(-))2 (where N^N = 2,2'-bipyridine, bpy; 4,4'-dimethylbipyridine, dmbpy; 1,10-phenanthroline, phen) as corners and tripyrazole functional ligands () as linkers, a series of highly-positively-charged tripyrazolate-bridged metallo-cages with different conformations and cavities such as [Pd6L2](6+) ( or , where L = L(1) or L(5)), [Pd10L(2)4](10+) (, and , where L = L(2) or L(4)) and [Pd12L4](12+) ( or , where L = L(3) or L4) have been synthesized through a di-metal coordination directed self-assembly with spontaneous deprotonation of the tripyrazole ligands in aqueous solution. These complexes have been fully characterized by (1)H and (13)C NMR, cold-spray ionization or electron spray ionization mass spectrometry (CSI-MS, ESI-MS) and elemental analysis. Complexes , , , and have also been determined by single-crystal X-ray diffraction structural analysis. In the case of complex , six PF6(-) anions were encapsulated within the cavity composed of adjacent di-Pd corners.

From {Au(I)···Au(I)}-coupled cages to the cage-built 2-D {Au(I)···Au(I)} arrays: Au(I)···Au(I) bonding interaction driven self-assembly and their Ag(I) sensing and photo-switchable behavior.

Metal-metal bonding interactions have been used to generate a number of unique supramolecular assemblies with fascinating functions. We presented here a new class of gold(I)-containing metallosupramolecular cages and cage-built two-dimensional (2-D) arrays of {Au8L2}n (n = 1 or ∞, L = tetrakis-dithiocarbamato-calix[4]arene, TDCC), 1-3, which are constructed from the self-assembly of deep-cavitand calix[4]arene-based supramolecular cages consisting of octanuclear Au(I) motifs. Synchrotron radiation X-ray diffraction structural analyses of 1-3 revealed their quadruple-stranded helicate dimeric cage structure and the presence of 2-D arrays of cages linked together by inter- and intramolecular Au(I)···Au(I) interactions. Electronic absorption and emission studies of complexes 1-3 indicated the occurrence of a programmable self-assembly process in a concentration-dependent stepwise manner with the links built via aurophilic interactions. These novel gold(I) supramolecular cages exhibited green phosphorescence and have been shown to serve as highly selective proof-of-concept luminescent sensors toward Ag(I) cation among various competitive transition-metal ions.

Synthesis, structural characterization and luminescent properties of a series of Cu(I) complexes based on polyphosphine ligands.

A series of Cu(I) complexes with a [Cu(NN)(PP)](+) moiety, [Cu(phen)(pba)](BF(4)) (1a), [Cu(2)(phen)(2)(pbaa)](BF(4))(2) (2a), [Cu(2)(phen)(2)(pnaa)](BF(4))(2) (3a), [Cu(2)(phen)(2)(pbbaa)](BF(4))(2) (4a), [Cu(dmp)(pba)](BF(4)) (1b), [Cu(2)(dmp)(2)(pbaa)](BF(4))(2) (2b), [Cu(2)(dmp)(2)(pnaa)](BF(4))(2) (3b) and [Cu(2)(dmp)(2)(pbbaa)](BF(4))(2) (4b) (phen = 1,10-phenanthroline, dmp = 2,9-dimethyl-1,10-phenanthroline, pba = N,N-bis((diphenylphosphino)methyl)benzenamine, pbaa = N,N,N',N'-tetrakis((diphenylphosphino)methyl)benzene-1,4-diamine, pnaa = N,N,N',N'-tetrakis((diphenylphosphino)methyl)naphthalene-1,5-diamine and pbbaa = N,N,N',N'-tetrakis((diphenylphosphino)methyl)biphenyl-4,4'-diamine), were rationally designed and synthesized. These complexes were characterized by (1)H and (31)P NMR, electrospray mass spectrometry, elemental analysis and X-ray crystal structure analysis. Introduction of different central arene spacers (phenyl, naphthyl, biphenyl) into ligands, resulting in the size variation of these complexes, aims to tune the photophysical properties of the complexes. Each Cu(I) ion in these complexes adopts a distorted tetrahedral geometry constructed by the chelating diimine and phosphine groups. Intermolecular C-H···π and/or π···π interactions are involved in the solid states. The dmp-containing complex exhibits better emission relative to the corresponding phen complex due to the steric encumbrance of bulky alkyl groups. Furthermore, for complexes with identical diimine but different phosphine ligands, the tendency of increased emission lifetime as well as blue-shifted emission in the solid state follows with the decrease in size of complexes. Intermolecular C-H···π interactions have an influence on the final solid state photophysical properties through vibrationally relaxed non-radiative energy transfer in the excited state. Smaller-sized complexes show better photophysical properties due to less vibrationally relaxed behavior related to flexible C-H···π bonds. Nevertheless, the tendency for increased quantum yield and emission lifetime, as well as blue-shifted emission in dilute solution goes with the increase in size of complexes. The central arene ring (phenyl, naphthyl or biphenyl) has an influence on the final photophysical properties. The larger the π-conjugated extension of central arene ring is, the better the photophysical properties of complex are. The rigid and large-sized complex 3b, with a high quantum yield and long lifetime, is the best luminophore among these complexes.

{µ-trans-N,N'-Bis[(diphenyl-phosphan-yl)meth-yl]benzene-1,4-diamine-κP:P'}bis-{(acetonitrile-κN)[dipyrido[3,2-a:2',3'-c]phenazine-κN,N]copper(I)} bis-(tetra-fluoridoborate).

In the centrosymmetric dinuclear title compound, [Cu(2)(C(2)H(3)N)(2)(C(18)H(10)N(4))(2)(C(32)H(30)N(2)P(2))](BF(4))(2), the Cu(I) centre is coordinated by two N atoms from a dipyridophenazine ligand, one P atom from an N,N'-bis-[(diphenyl-phosphan-yl)meth-yl]benzene-1,4-diamine (bpbda) ligand, and one N atom from an acetonitrile mol-ecule in a distorted tetra-hedral geometry. The bpbda ligand, lying on an inversion center, bridges two Cu(I) centres into a Z-shaped complex. Intra-molecular π-π inter-actions between the dipyridophenazine ligand and the benzene ring of the bpbda ligand are observed [centroid-centroid distance = 3.459 (3) Å]. The crystal structure also involves inter-molecular π-π inter-actions between the dipyridophenazine ligands [centroid-centroid distance = 3.506 (3) Å], which lead to a one-dimensional supra-molecular structure.

Tetra-aqua-bis(2-methyl-benzimidazolium-1,3-diacetato-κO)zinc(II) tetra-hydrate.

The asymmetric unit of the title compound, [Zn(C(12)H(11)N(2)O(4))(2)(H(2)O)(4)]·4H(2)O, contains one-half of the complex mol-ecule and two uncoordin-ated water mol-ecules. The four water O atoms in the equatorial plane around the Zn(II) centre ( symmetry) form a distorted square-planar arrangement, while the distorted octa-hedral coordination geometry is completed by the O atoms of the zwitterionic 2-methyl-benzimidazolium-1,3-diacetate ligands in the axial positions. The benzimidazole ring system is planar, with a maximum deviation of 0.041 (3) Å. Intra-molecular O-H⋯O hydrogen bonding results in the formation of a non-planar six-membered ring. In the crystal structure, strong intra- and inter-molecular O-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional network. π-π contacts between benzimidazole rings [centroid-centroid distance = 3.899 (1) Å] may further stabilize the structure.

[µ-N,N'-Bis(diphenyl-phosphinometh-yl)benzene-1,4-diamine-κP:P']bis-[(2,2'-bipyridine-κN,N')silver(I)] bis-(per-chlorate) acetone disolvate.

The title complex, [Ag(2)(C(10)H(8)N(2))(2)(C(32)H(30)N(2)P(2))](ClO(4))(2)·2CH(3)COCH(3), is a centrosymmetric dimer with pairs of Ag(I) atoms bridged by N,N'-bis-(diphenyl-phosphinometh-yl)ben-zene-1,4-diamine ligands. In addition, each Ag(I) atom is coordin-ated by one chelating 2,2'-bipyridine ligand, giving a distorted trigonal coordination environment.