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(1-methyl-1H-benzo[d]imidazol-2-yl) methanol (Hmbm) reacts with Mn(ClO4)2·6H2O to form heptanuclear disks [Mn7(mbm)12]·2(ClO4) (1) under ambient conditions. The heptanuclear cluster was previously described as a double calix unit with the hydroxides in the middle. The seven Mn(II) ions are essentially coplanar as expected for all edge-sharing octahedra, which can be intituled as a segment of Mg(OH)2 layer of brucite, so it is a symmetric disk. ESI–MS of crystals showed its stability in solution. Time-dependent mass spectrometry (MS) from solutions at different period of the assembly reveal a hierarchical sequence, [MnIII(mbm)2]+ → [MnII2(mbm)3]+ → [MnII4(mbm)6(ClO4)]+ → [MnIIIMnII6(mbm)12(ClO4)2]+. [ABSTRACT FROM AUTHOR]

The assembly sequence of the coordination cluster [Zn5(H2L n)6](NO3)4]⋅8 H2O⋅2 CH3OH ( Zn5, H3L n=(1,2-bis(benzo[d]imidazol-2-yl)-ethenol) involves in situ dehydration of 1,2-bis(benzo[d]imidazol-2-yl)-1,2-ethanediol (H4L) through the formation of the [Zn(H3L)2]+ monomer, dimerization to [Zn2(H3L)2]+, dehydration of the ligand to [Zn2(H2L n)2]+, and the final formation of the pentanuclear cluster. The cluster has the following special characteristics: 1) high stability in both refluxing 37 % HCl and 27 % NH3, 2) low cytotoxicity, and 3) pH-sensitive fluorescence in the visible-to-near-infrared (Vis/NIR) region in the solid state and in solution. We have applied it as a fluorescent probe both in vivo and in vitro. Its H-bonding ability is the key to its affinity and selectivity for imaging lysosomes in HeLa cells and tumors in male BALB/C mice. It provides a new type of sensitive and biocompatible fluorescent probe for detecting small tumors (13.5 mm3). [ABSTRACT FROM AUTHOR]

The assembly sequence of the coordination cluster [Zn5(H2L n)6](NO3)4]⋅8 H2O⋅2 CH3OH ( Zn5, H3L n=(1,2-bis(benzo[d]imidazol-2-yl)-ethenol) involves in situ dehydration of 1,2-bis(benzo[d]imidazol-2-yl)-1,2-ethanediol (H4L) through the formation of the [Zn(H3L)2]+ monomer, dimerization to [Zn2(H3L)2]+, dehydration of the ligand to [Zn2(H2L n)2]+, and the final formation of the pentanuclear cluster. The cluster has the following special characteristics: 1) high stability in both refluxing 37 % HCl and 27 % NH3, 2) low cytotoxicity, and 3) pH-sensitive fluorescence in the visible-to-near-infrared (Vis/NIR) region in the solid state and in solution. We have applied it as a fluorescent probe both in vivo and in vitro. Its H-bonding ability is the key to its affinity and selectivity for imaging lysosomes in HeLa cells and tumors in male BALB/C mice. It provides a new type of sensitive and biocompatible fluorescent probe for detecting small tumors (13.5 mm3). [ABSTRACT FROM AUTHOR]

The impacts of advanced traveler information system’s (ATIS’s) penetration and compliance rates on network performances during hybrid traffic emergency evacuation are investigated in a degraded road network. Before traffic incident a Path-Size Logit (PSL) route choice model is integrated with constraints on the level of service (LOS) of traffic to formulate a bilevel programming model. It aims at minimizing traffic demand in road network which may locally deteriorate the LOS. The lower level is a PSL-stochastic user equilibrium model for multiple classes of users. During the ongoing incident, a multiobjective multiuser-class stochastic optimization model is established with the objectives of maximizing evacuation reliability and minimizing expected network travel time. Furthermore, computations and analyses are completed for five designated scenarios including a method proposed in previous literature. The results show that the evacuation reliability and different kinds of total expected travel time costs regularly increase with emergency traffic’s ATIS compliance rate and decrease with general traffic’s ATIS penetration rate. The research will help improve transport network performance when considering ATIS’s effect on hybrid traffic. [ABSTRACT FROM AUTHOR]

Abstract: A new hexanuclear cadmium(II) complex of Cd6(pyim)4(Hpyim)6(sal)4 (Hpyim=2-pyridylbenzimidazole, H2sal=salicylic acid) (1) has been synthesized under hydrothermal condition and characterized by element analysis, FT-IR spectroscopy and luminescent analysis. X-ray crystallographic studies reveal that complex 1 displays a novel hexanuclear unit in which six cadmium ions are bridged by deprotonated salicylic and pyridylbenzimidazole ligands. In 1, the hexanuclear units are further assembled into a 3D supramolecular framework by hydrogen bonding, π–π and C−H⋯π stacking interactions. In the solid state, complex 1 shows blue photoluminescent property at room temperature. [Copyright &y& Elsevier]

A zinc(II) coordination polymer, [Zn4(o-bda)4(p-pbim)4]n (1) (p-pbim = 4-pyridylbenzimidazole, o-bda2- = o-phenylenediacetic acid dianion), has been synthesized by hydrothermal method and characterized by elemental analysis, IR, TG, photoluminescence and X-ray single crystal diffraction. Complex 1 crystallizes in a monoclinic system and space group P21/n, with a = 14.231(3) Å, b = 16.257(4) Å, c = 16.794(4) Å, β = 100.262(1)°, and Z = 8; R1 for 6475 observed reflections [I > 2σ(I)] was 0.0420. Complex 1 shows a bi-chain structure fabricated by the tetranuclear zinc unit. Two zinc(II) ions are five coordinate with distorted trigonal-bipyramid geometry; the other two zinc(II) ions are four coordinate with distorted tetrahedral geometry. Complex 1 builds the 1-D bi-chain structure with two different subrings A and B, which are 32-member and 14-member rings, respectively. There exists a 2-D supramolecular network linked by hydrogen-bonding interactions (2.695 and 2.807 Å). A 3-D supramolecular network is further constructed by non-covalent interactions between the 1-D bi-chain structure. The TG/DTG shows that the chain skeleton is thermally stable to 356°C. Blue fluorescent emission of the complex was determined at 404 nm in the solid state with short decay lifetime of 1.67 ns. [ABSTRACT FROM AUTHOR]

The silver and acid hydrogen atoms in the crystal structure of [Ag(pa)(Hpa)]n (Hpa = 3-(1H-benzimidazol-2-yl) propionic acid-N) both lie on special positions of -1 site symmetry; the silver atom shows linear coordination [Ag-N = 2.109(3) Å, N-Ag-N = 180°]. The 'acid hydrogen' links molecules into a linear chain, and hydrogen bonds between the nitrogen-bound hydrogen atom and the carbonyl oxygen atom of an adjacent chain furnish a three-dimensional supramolecular structure. The compound, C20H19AgN4O4, belongs to the triclinic space group P1 [a = 6.536(7), b = 8.127(9), c = 9.051(1) Å; α = 81.692(2), β = 82.819(2), γ = 87.229(2)°], and there is one formula unit in the unit cell. [ABSTRACT FROM AUTHOR]

Abstract: Two new 3D zinc carboxylates Zn2(suc)(ina)2 (1) (suc=succinate, ina=isonicotinate) and Zn2(fum)(ina)2 (2) (fum=fumarate) have been synthesized under the hydrothermal condition and characterized by the single crystal X-ray diffractions. Both complexes 1 and 2 featuring the [Zn2(CO2R)4] subunit (SBU) formed by mixed tetracarboxylate, interlinked by carboxylate-aromatic amine ligands (ina) to construct a 2D (4,4) sheet, which are further pillared by rigid or flexible dicarboxylates ligands (suc or fum) into 3D framework. The topology of 1 and 2 can be related to the cubic α-Po twofold interpenetrating lattice. Thermogravimetric analyses demonstrate the similar one-step thermal decomposition process with the tolerate temperature ca. 400°C of complexes 1 and 2 resulted from the parallel structure motifs and high stability of them. [Copyright &y& Elsevier]

Abstract: Four dimeric and polymeric coordination compounds [Zn2(bimb)2(pdc)2]·6H2O (1), [Cd2(bimb)2(tp)2]·H2O (2), [Cd(bimb)(ada)] (3) and [Co(bimb)(ada)] (4) (bimb, 4,4′-bis(imidazol-1-ylmethyl)biphenyl; pdc, pyridine-2,6-dicarboxylate; tp, terephthalate and ada, adipate) have been synthesized under hydrothermal conditions. Complex 1 is a discrete dinuclear metallomacrocycle featuring a 34-membered ring, in which the flexible bimb ligand acts as syn-conformation. While complexes 2–4 are 3D network structures connected by bimb and dicarboxylate ligands, the bimb ligand displays anti-confromation. [Copyright &y& Elsevier]

Abstract: A new cobalt(II) phosphonate, [enH2]0.5[Co(pa)(H2O)]·H2O (1) (H3pa=hydroxy-phosphono-acetic acid, HO2CCH(OH)PO3H2; en=ethylenediamine), has been hydrothermally synthesized and structurally characterized. Compound 1 has a honeycomb-like layer structure which is composed of CoO6 octahedra and μ3-pa ligands with the protonated en and lattice water molecules stabilized between the layers. Magnetic studies indicate that 1 shows weak ferromagnetic behavior, spin-glass behavior, and metamagnetic behavior. [Copyright &y& Elsevier]

One mixed-ligand complex of [Mn2(mpa)2(2,2′-bpy)2]n (1) (mpa=m-phthalate and 2,2′-bpy=2,2′-bipyridine) has been synthesized and structurally established by single-crystal X-ray diffraction. It consists of one-dimensional ribbons featuring carboxylate-bridged dinuclear units. The one-dimensional ribbons are assembled into three-dimensional networks by π–π stacking interactions. It was stable in air up to ca. 245 °C. The magnetic measurements suggest that the polymer gives weak antiferromagnetic behavior. [Copyright &y& Elsevier]

cobalt(A novel three dimensional (3D) polymer, [Co2(hypa)2(4,4′-bipy)] (1) (H2hypa = hydroxy-phenyl-acetic acid, 4,4′-bipy = 4,4′-bipyridine), featuring pentacoordinate, dimeric cobalt(II) as subunits have been prepared, which shows low-dimensional antiferromagnetic ordering blow 15.2 K (TN). [ABSTRACT FROM AUTHOR]

• Study an evacuation problem considering the dynamics and routing of buses and cars. • A bi-directional multilane conflict-eliminating cell transmission model (BCECTM). • A new evacuation optimization model is proposed by integrating the BCECTM and SDVRP. • The model describes trajectories and dynamics, and improves bus capacity utilization. This paper studies dynamic evacuation optimization in the context of a new cell transmission with the split delivery vehicle routing problem (SDVRP) of multiple modes of buses and cars. A bi-directional multilane conflict-eliminating cell transmission model (BCECTM) is proposed to simulate the mixed traffic dynamic evacuation process on links and at intersections. The method of SDVRP is applied to manage dynamic evacuation demands and optimize the routing of multiple modes. The mechanisms of vehicle transmission, traveling trajectory, and residual capacity updating are depicted based on the models of BCECTM and SDVRP; thus, a mathematical programming model aiming to minimize the total evacuation time is established by integrating the BCECTM and SDVRP. A genetic algorithm with a chromosome position-coding scheme is designed to solve the evacuation optimization model. Case studies show that the proposed model can reasonably assign evacuation demands that gather at some sites around the event to, and effectively evacuate people by, buses and cars so that the capacities of buses are fully utilized, and can generate optimal vehicle traveling trajectories to improve the evacuation performance. Furthermore, the evacuation and congestion degree under different demand levels and different arrival distributions are analyzed with meaningful conclusions. [ABSTRACT FROM AUTHOR]

Domino reaction of benzo[d]thiazole‐2‐methylamine (S1) has been developed in the presence of MnCl2 ⋅ 4H2O, leading to tetrasubstituted pyrrole coordinated dinuclear Mn(II) complex 1 ([MnClP]2, P−=2,3,4,5‐tetrakis(benzo[d]thiazol‐2‐yl)pyrrol‐1‐ide). The reaction process has been studied by assigning a series of intermediates based on time‐dependent mass spectrometry, control experiments, crystallography, and density functional theory (DFT) theoretical calculation. A plausible mechanism involving an unprecedented divergent‐convergent domino sequence has been proposed. Compound S1 could be activated by MnCl2 ⋅ 4H2O via coordination, which divergently produces two intermediates imine II (1‐(benzo[d]thiazol‐2‐yl)‐N‐(benzo[d]thiazol‐2‐ylmethyl)methanimine) and alkene C (1,2‐bis(benzo[d]thiazol‐2‐yl)ethene) through oxidative self‐condensation and free radical coupling followed by elimination, respectively. They could then react with each other convergently via formal [3+2] cycloaddition to give deprotonated tetrasubstituted pyrrole coordinated intermediate [MnClP] after aromatization. Dimerization of [MnClP] produces the final product 1. Three C−C bonds and one C−N bond are formed through this six‐step domino sequence. The corresponding organic skeleton (HP: 2,2′,2′′,2′′′‐(1H‐pyrrole‐2,3,4,5‐tetrayl)tetrakis(benzo[d]thiazole)) has been obtained from 1 and shows a higher fluorescent quantum yield (52 %) than the reported 3,4‐diphenyl substituted analogue 2,2′‐(3,4‐diphenyl‐1H‐pyrrole‐2,5‐diyl)bis(benzo[d]thiazole) (DPB) (42 %). [ABSTRACT FROM AUTHOR]

• Eight β-diphenyl substituted cyclopentadithiophene (CPD) derivatives with C s and C 2 symmetry and four unsubstituted CPDs were designed. • Different roles of phenyl, fluorine, and dicyanomethylene substitution, the α and β positions of phenyl on the thiophene ring were revealed. • Single-crystal structure of CPD derivatives was predicted theoretically. • Reorganization energies, charge transfer integrals, charge carrier mobilities were systematically studied. • Semiconductor nature and performance could be tuned upon molecule design. Eight cyclopentadithiophene (CPD) based semiconductors are designed by moving phenyl/fluorine-phenyl groups from α to β positions of thiophenes of CPD. The semiconductor performances of these CPD derivatives with Cs and C 2 symmetry (termed as CPD' and CPD", respectively) and their unsubstituted CPD backbones are analyzed systematically through DFT calculations. Some CPD'/CPD" compounds show better charge transfer mobility than CPD. We analyze in detail the factors influencing the semiconductor nature of these CPD derivatives and their charge carrier mobilities, revealing the different roles of fluorine and dicyanomethylene and of the α and β position of phenyl on the thiophene rings. Our findings can be generalized to broader classes of organic semiconductors and are expected to contribute to the rational design of n-type semiconductors based on CPDs. [ABSTRACT FROM AUTHOR]

A new glass forming method is essential for broadening the scope of liquid and glassy metal–organic frameworks due to the limitations of the conventional melt-quenching method. Herein, we show that in situ mechanical vibration can facilitate the framework melting at a lower temperature and produce glassy metal–organic frameworks (MOFs) with unique properties. Using zeolitic imidazolate framework (ZIF)-62 as a concept-proofing material, in situ mechanical vibration enables low-temperature melting at 653 K, far below its melting point (713 K). The resultant vibrated ZIF-62 glass exhibited a lower glass transition temperature of 545 K, improved gas accessible porosity, and pronounced short-to-medium range structures compared to the corresponding melt-quenched glass. We propose that vibration-facilitated surface reconstruction facilitates pre-melting, which could be the cause of the lowered melting temperature. The vibration assisted method represents a new general method to produce MOF glasses without thermal decomposition. [ABSTRACT FROM AUTHOR]

An unexpected dominance of the coordination affinity of the sulfate anion over those of two organic chelating ligands, (1-methyl-1H-benzo[d]imidazol-2-yl)methanol (Hmbm) and pyridin-2-ylmethanamine (pma), was observed during the study of the solvothermal assembly of [Co11(mbm)6(pma)2(SO4)8(H2O)6(CH3OH)6]·5CH3OH (1), from CoSO4·7H2O at 100 °C in methanol. ESI-MS of solutions at different periods of the assembly reveal a hierarchical sequence, [Co1] → [Co2] → [Co3] → [Co4] → [Co5] → [Co9], where the lower nuclearity species are richer in Co2+ and SO42− before the inclusion of more mbm ligands at the last step. Its crystal structure consists of an almost symmetrical wheel of nine cobalt atoms, [Co9(mbm)6(SO4)8(H2O)6] in edge-sharing octahedral coordination arranged in triangles with two peripheral dangling [Co(pma)(CH3OH)3]. The sulfate ions exhibit three different coordination modes, two in μ6-, two in μ3- and four as μ2-bridging. Its thermal, optical and magnetic properties are also reported. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A domino ring‐opening and coupling of imidazolyl annulated heterocycles 1 (1a: 4‐methyl‐1‐(1‐methyl‐1H‐benzo[d]imidazol‐2‐yl)‐4H‐ benzo[d]imidazo[1,5‐a]imidazole, 1b: 1‐(1,5‐dimethyl‐1H‐benzo[d]imidazol‐2‐yl)‐4,7‐dimethyl‐4H‐benzo[d]imidazo[1,5‐a]imidazole) with dioxygen was developed at solvothermal condition, leading to conjugated 1,2‐diamidoalkenes derivatives 2 ((E)‐ArCONHArC=CArNHCOAr (Ar: 1‐methyl‐1H‐benzo[d]imidazolyl (2a), 1,5‐dimethyl‐1H‐benzo[d]imidazolyl (2b))) as single crystals directly. The reaction process was tracked by electrospray ionization mass spectrometry (ESI‐HRMS) and a series of reaction intermediates are detected. 18O2 labeling experiment verified the source of oxygen in 2. Combining evidence from control experiments, nuclear magnetic resonance (NMR) tracking, and crystallography, a seven‐step reaction pathway involving oxygen addition, ring opening, Friedel‐Crafts alkylation, oxidation, and dehydration was proposed and further supported by DFT calculation. [ABSTRACT FROM AUTHOR]

Pd(ii)-Catalyzed direct C(sp3)–H germylation of α-AA derivatives with the assistance of a bidentate auxiliary for the efficient synthesis of β-germyl-α-amino amides is reported. This protocol features good generality for primary and secondary C–H bonds of aliphatic amides. Mechanistic studies show that a crucial five-membered palladacycle intermediate may play a key role in this process. [ABSTRACT FROM AUTHOR]

Glassy and liquid state metal–organic frameworks (MOFs) are emerging type of materials subjected to intense research for their rich physical and chemical properties. In this report, we obtained the first glassy MOF that involves metal‐carboxylate cluster building units via multi‐stage structural transformations. This MOF is composed of linear [Mn3(COO)6] node and flexible pyridyl‐ethenylbenzoic linker. The crystalline MOF was first perturbed by vapor hydration and thermal dehydration to give an amorphous state, which can go through a glass transition at 505 K into a super‐cooled liquid. The super‐cooled liquid state is stable through a wide temperature range of 40 K and has the largest fragility index of 105, giving a broad processing window. Remarkably, the super‐cooled liquid can not only be quenched into glass, but also recrystallize into the initial MOF when heated to a higher temperature above 558 K. The mechanism of the multi‐stage structural transformations was studied by systematic characterizations of in situ X‐ray diffraction, calorimetry, rheological, spectroscopic and pair‐distribution function analysis. These multi‐stage transformations not only represent a rare example of high temperature coordinative recognition and self‐assembly, but also provide new MOF processing strategy through crystal‐amorphous‐liquid‐crystal transformations. [ABSTRACT FROM AUTHOR]

Glassy and liquid state metal–organic frameworks (MOFs) are emerging type of materials subjected to intense research for their rich physical and chemical properties. In this report, we obtained the first glassy MOF that involves metal‐carboxylate cluster building units via multi‐stage structural transformations. This MOF is composed of linear [Mn3(COO)6] node and flexible pyridyl‐ethenylbenzoic linker. The crystalline MOF was first perturbed by vapor hydration and thermal dehydration to give an amorphous state, which can go through a glass transition at 505 K into a super‐cooled liquid. The super‐cooled liquid state is stable through a wide temperature range of 40 K and has the largest fragility index of 105, giving a broad processing window. Remarkably, the super‐cooled liquid can not only be quenched into glass, but also recrystallize into the initial MOF when heated to a higher temperature above 558 K. The mechanism of the multi‐stage structural transformations was studied by systematic characterizations of in situ X‐ray diffraction, calorimetry, rheological, spectroscopic and pair‐distribution function analysis. These multi‐stage transformations not only represent a rare example of high temperature coordinative recognition and self‐assembly, but also provide new MOF processing strategy through crystal‐amorphous‐liquid‐crystal transformations. [ABSTRACT FROM AUTHOR]

In the title compound, [Co(C19H12N5)2], each CoII atom occupies a position of high site symmetry, 222, and is coordinated by the six N atoms [Co—N = 2.085 (4)–2.157 (3) Å] from two tridentate 2-[6-(1 H-benzimidazol-2-yl)-2-pyrid­yl]­benz­imi­dazol­ide ligands in a distorted octa­hedral geometry. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, C7H6Br2O2·0.5H2O, contains two independent 3,5-dibromo­salicyl alcohol mol­ecules and one water mol­ecule. The salicyl alcohol mol­ecules inter­act with each other and with the water mol­ecule through O—H⋯O hydrogen bonding, giving rise to a layer structure. [ABSTRACT FROM AUTHOR]

The title compound, [Zn(NO3)(C8H8N2O)2]NO3·H2O, consists of a tris-chelated zinc cation and a nitrate anion, along with an uncoordinated water mol­ecule. These inter­act through O—H⋯O and N—H⋯O hydrogen bonds, giving rise to a three-dimensional network structure. The ZnII ion has an octa­hedral coordination. [ABSTRACT FROM AUTHOR]

The two chromen-3-yl substituents at the 2- and 3-positions of the 1,4-dihydroxy­benzene in the title dimethyl­formamide (DMF) tris­olvate, C24H14O10·3C3H7NO, are aligned at 67.1 (1) and 69.8 (1)° with respect to the central aromatic ring. The 1-hydr­oxy group serves as a hydrogen-bond donor to a DMF whereas the substituent at the 3-position functions as a hydrogen-bond donor to two DMF mol­ecules. The other three hydr­oxy groups inter­act with donor sites of adjacent mol­ecules, generating a three-dimensional network architecture. [ABSTRACT FROM AUTHOR]

The title compound, [Cd(C3H6NO5P)(H2O)2] n, is a three-dimensional polymeric complex. The asymmetric unit contains one Cd atom, one N-(phosphono­methyl)glycine zwitterion [(O−)2OPCH2NH2+CH2COO−] and two water mol­ecules. The coordination geometry is a distorted CdO6 octa­hedron. Each N-(phosphono­methyl)glycine ligand bridges four adjacent water-coordinated Cd cations through three phospho­nate O atoms and one carboxyl­ate O atom, like a regular PO43− group in zeolite-type frameworks. One-dimensional zigzag (–O—P—C—N—C—C—O—Cd–) n chains along the [101] direction are linked to one another via Cd—O—P bridges and form a three-dimensional network motif with three types of channel systems. The variety of O—H⋯O and N—H⋯O hydrogen bonds is likely to be responsible for stabilizing the three-dimensional network structure and preventing guest mol­ecules from entering into the channels. [ABSTRACT FROM AUTHOR]

In the title compound, [Cd(C9H6O5)(C10H8N2)(H2O)] n, the CdII atom is coordinated in a distorted octa­hedral fashion by two carboxyl­ate groups (one in a monodentate and one in a bidentate fashion) from two 4-carboxyl­ato­phenoxy­acetate anions, two N atoms from a 2,2′-bipyridine ligand and one aqua ligand. The structure is a helix with a long pitch of 16.441 (5) Å. A three-dimensional supra­molecular network is further constructed through π–π stacking and hydrogen-bonding inter­actions between the helices. [ABSTRACT FROM AUTHOR]

We present the construction of a M2L4‐type metal‐organic nanocage featuring four endohedral Feringa's motor motifs and its adaptive encapsulation towards a C60 guest molecule. The structure of the cage, though complicated on the 1H NMR spectrum due to the adoption of mixed ligands, was unambiguously characterized with a combination of ESI‐MS, 2D DOSY, 13C NMR and particularly the SAXS technique. The molecular motor within the cage demonstrated similar photophysical properties to the uncoordinated one, indicating the motor's function was not compromised when it was anchored in such a confined nanospace. Furthermore, the nanocage showed good guest encapsulation ability towards C60, and a guest induced‐fit behavior of the cage was revealed based on the extensive SAXS analysis and molecular dynamics simulation. The adaptive motorized nanocage reported here represents one of the very few examples of integrating individual motors into a discrete nanoconfined system and offers prospects to achieve its non‐equilibrium functions. [ABSTRACT FROM AUTHOR]

We report a phosphine-directed ruthenium-catalyzed C8-selective alkylation of naphthalenes with alkenes. This protocol provides straightforward access to a large library of electron-rich C8-alkyl substituent 1-naphthphosphines, which outperformed common commercial phosphines and their precursors in the Pd-catalyzed Suzuki–Miyaura coupling of aryl bromides with alkylboronic acid. [ABSTRACT FROM AUTHOR]

The research on metal–organic frameworks (MOFs) has been developing at an extraordinary pace in its two decades of existence, as judged by the exponential growth of novel structures and the constant expansion of its applicability and research scope. A major part of the research and its success are due to the vital role of the concept of mixed organic ligands in the design, tuning and functions. This perspective, therefore, reviews the recent advances in MOFs based on this concept, which is generally based on employing a small polydentate ligand (here labelled as “nodal ligand”) to form either clusters, rods or layers, which are then connected by a second ditopic linker ligand to form the framework. The structures of the materials can be grouped into the following three categories: layer-spacer (usually known as pillared-layer), rod-spacer, and cluster-spacer based MOFs. Depending on the size and geometry of the spacer ligands, interpenetrations of frameworks are occasionally found. These MOFs show a wide range of properties such as (a) crystal-to-crystal transformations upon solvent modifications, post-synthetic metal exchange or ligand reactions, (b) gas sorption, solvent selectivity and purification, (c) specific catalysis, (d) optical properties including colour change, luminescence, non-linear optic, (e) short- and long range magnetic ordering, metamagnetism and reversible ground-state modifications and (f) drug and iodine carriers with controlled release. In the following, we will highlight the importance of the above concept in the design, tuning, and functions of a selection of existing MOFs having mixed organic ligands and their associated structures and properties. The results obtained so far using this concept look very promising for fine-tuning the pore size and shape for selective adsorption and specificity in catalytic reactions, which appears to be one way to propel the advances in the application and commercialization of MOFs. [ABSTRACT FROM AUTHOR]

A one-dimensional ribbon copper(II) complex, {CuII3(L)2(OH)2(NO3)2(H2O)4}n (1, HL=1-methyl-2-(3H-[1-3]triazol-4-yl)-1H-benzimidazole), has been hydrothermally synthesized from in situ generated HL at 160°C. Its structure is very unusual that all ligands and Cu(II) ion are distributed in the same horizontal plane in each chain. Two ligands chelate and bridge two Cu(II) ions to form a planar metalloligand which is then connected to each other through coordination to another Cu(II) to give the 2+1 infinite chain structure. Axial coordination sites of the Cu(II) are taken up by nitrate and water. Hydrogen bonding and π-π stacking interactions between chains intensify the stability of 3D supramolecular architecture. This particular structure is the result of a cooperative effect associated with the Jahn-Teller distortion of the copper(II) ion, the hydrogen bonding and π-π stacking interactions. Its magnetic properties indicate antiferromagnetic interactions between copper(II) within the chain. [ABSTRACT FROM AUTHOR]

We designed two near‐infrared (NIR) lanthanide complexes [(L)2‐Nd(NO3)3] (L=TPE2‐BPY for 1, TPE‐BPY for 2) by employing aggregation‐induced emission (AIE)‐active tetraphenylethylene (TPE) derivatives as sensitizers, which possessed matched energy to NdIII, prevented competitive deactivation under aggregation, even shifted the excitation window toward 600 nm by twisted intramolecular charge transfer. Furthermore, benefiting from the 4 f electron shielding effect and antenna effect, the enhanced excitation energies of the AIE‐active sensitizers by structural rigidification transferred into the inert NdIII excited state through 3LMCT, affording the first aggregation‐induced phosphorescence enhancement (AIPE)‐active discrete NIR‐emitting lanthanide complexes. As 1 equipped with more AIE‐active TPE than 2, L→Nd energy transfer efficiency in the former was higher than that in the latter under the same conditions. Consequently, the crystal of 1 exhibited one of the longest lifetimes (9.69 μs) among NdIII‐based complexes containing C−H bonds. [ABSTRACT FROM AUTHOR]

In order to comparing and explaining the experimental infrared, electronic absorption and emission spectra of tris (4‐methyl‐1‐(1‐methyl‐1H‐benzo [d] imidazol‐2‐yl) −4H‐benzo [d] imidazo[1,5‐a]imidazol‐3‐yl) methyl (L6), density functional theory calculations were performed to systematically study the spectral properties of several species with different electronic states (L6+, L6 and HL6+), as well as the axial substituted derivative with methoxy group (L6‐OCH3). The main peaks in the vibrational, electronic absorption and emission spectra were assigned in detail. Roles of molecular electronic states and axial substitution on the spectral properties are revealed. The calculated spectra are compared with experimental results to distinguish the nature of L6 in crystal and solvent. This work combing experiment and theoretical calculations would be good example for clarifying molecular electronic states and, thus, promising the practice application of such kind of novel molecules. [ABSTRACT FROM AUTHOR]

The salts {[Ln2Ln*(Hhmq)3(OAc)3(hfac)2]+ [Ln*(hfac)3(OAc)(MeOH)]−} (Hhmq=2‐methanolquinolin‐8‐oxide, hfac=hexafluoroacetylacetonate; Ln, Ln*=Er, Gd, Yb) feature a discrete heteronuclear cation consisting of two types of lanthanide atoms. The quinolinoxy O‐atom serves as a μ2‐bridge to two Ln atoms and as a μ3‐bridge to all three atoms, with metal⋅⋅⋅metal distances being around 3.7 Å. For 1 ([Yb2Er]+), near‐infrared downshifted luminescence is switched to competitive upconversion luminescence upon irradiation by a 980 nm laser under an extremely low excitation power (0.288 W cm−2) through introduction of fluoride ions. The stability of 1 after addition of fluoride was confirmed by powder X‐ray diffraction and multistage mass spectrometry, associated with the 1H NMR of 6 ([La2Eu]+). More importantly, the at least 20‐fold enhancement of the quantum yield in non‐deuterated solvents at room temperature under low power densities (2 W cm−2) is the highest among the few molecular examples reported. [ABSTRACT FROM AUTHOR]

The salts {[Ln2Ln*(Hhmq)3(OAc)3(hfac)2]+ [Ln*(hfac)3(OAc)(MeOH)]−} (Hhmq=2‐methanolquinolin‐8‐oxide, hfac=hexafluoroacetylacetonate; Ln, Ln*=Er, Gd, Yb) feature a discrete heteronuclear cation consisting of two types of lanthanide atoms. The quinolinoxy O‐atom serves as a μ2‐bridge to two Ln atoms and as a μ3‐bridge to all three atoms, with metal⋅⋅⋅metal distances being around 3.7 Å. For 1 ([Yb2Er]+), near‐infrared downshifted luminescence is switched to competitive upconversion luminescence upon irradiation by a 980 nm laser under an extremely low excitation power (0.288 W cm−2) through introduction of fluoride ions. The stability of 1 after addition of fluoride was confirmed by powder X‐ray diffraction and multistage mass spectrometry, associated with the 1H NMR of 6 ([La2Eu]+). More importantly, the at least 20‐fold enhancement of the quantum yield in non‐deuterated solvents at room temperature under low power densities (2 W cm−2) is the highest among the few molecular examples reported. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Exploring pyrolysis process is an efficient way to study the relationship between molecular level of the precursor structure and electrocatalytic functional materials in practice. Here, the unique semi‐enclosed sector structure of Salophen ligands with highly symmetric N, N, O, O mode was introduced to construct binuclear Co complex [Co2(salophen)(Cl)2(C2H3N)] (compound 1), which provides preliminary theoretical basis for the efficient coreshell structure electrocatalysts obtained by pyrolysis regulation. Moreover, we adopted TG‐MS to real‐time track the pyrolysis process from precursors of binuclear Co complexes with Salophen ligand to efficient catalytic materials with core‐shell nanostructures. As expected, the 1‐600 sample achieves ultra‐low overpotential of 256 mV at 10 mA·cm–2 and high catalytic stability within 10 h in 1 mol/L KOH solution. This work highlights salophen‐ligated complex as excellent precursor material system for the analysis of pyrolysis evolution process, and provides an opportunity for targeted preparation of efficient oxygen evolution reaction (OER) nanocatalysts. [ABSTRACT FROM AUTHOR]

Abstract: A chiral cluster-based 3D coordination polymer [Co2(ca)(ina)2(H2O)] n (1, ca= d-(+)-camphorate, ina=isonicotinate), containing mixed geometries cobalt(II) dimers as subunit, featuring unique rugate [Co2(ina)2] n 2 n + 2D layers pillared by the ca ligands has been studied. The bridge modes and their intermolecular interactions of the mixed rigid planar ina and flexible bulky ca ligands display an interesting example of shape recognition in packing style of 3D frameworks. The bulky antiferromagnetic behavior of 1, mainly arises from the cooperative magnetic effect of the interdimers arrangement in the chiral 3D network based on the nature of the exchange modes of mixed multi-carboxylate bridges within the mixed geometric Co(II) dimer. [Copyright &y& Elsevier]

Abstract: Two bis-(1-arylliminomethylenyl-2-oxy-naphthalen) nickel complexes (aryl=2-methylphenyl, complex 1; aryl=2,6-diisoproylphenyl, complex 2) were reacted with alkylaluminium in presence of equimolar PPh3 and tested as catalysts in methyl methacrylate (MMA) polymerization. The two nickel catalysts can initiate polymerization of MMA with good to high activity, the highest activity reaching 1.1×105 g PMMA/(mol Ni·h) by less bulky complex 1 at 0.8mol/L of MMA, 400 of Al/Ni ratio and 0°C. In addition, the structures of nickel complexes and polymerization conditions, such as monomer concentration, polymerization temperature and Al/Ni molar ratio on catalytic activity of polymerization have great influences on catalytic activity and product properties. [Copyright &y& Elsevier]

A double‐ligands enabled ruthenium catalyzed C(sp2)−H arylation of dialkyl phosphines is described, which provides a straight access to aryl‐substituted dialkyl phosphine ligands. The combination of 1,3‐diketone and amino acid ligands is essential for this transformation. An important six‐membered cycloruthenium intermediate was successfully isolated and characterized by X‐ray diffraction. Mechanistic studies showed that the 1,3‐diketone promoted the process of oxidative addition of cycloruthenium intermediate. Some of modified CyJohnPhos ligands exhibited highly catalytic activity in palladium catalyzed C−N bond formation. [ABSTRACT FROM AUTHOR]

Extending new families of ABX3-type three-dimensional (3D) molecular perovskites based on diverse X-site molecular ligands is of interest in designing advanced hybrid materials for wide usage. Being a pseudo-halogen ligand, the thiocyanate anion is expected as an X-site bridge to construct 3D molecular perovskites, but has only yielded two pure inorganic instances so far. Herein, we report four new 3D SCN−-bridged molecular double perovskites with a general formula of A2[CdM′(SCN)6] (A/M′ = K+/Ni2+, Me2NH2+/Ni2+, Me2NH2+/Mn2+, Me3S+/Cd2+), including three unprecedented hybrid instances incorporating organic cations. A detailed comparison between these SCN−-bridged molecular perovskites and some azido-bridged analogues, on their host–guest interactions and structural distortions, revealed that the bent Cd–S–C angles in these SCN−-bridged molecular perovskites vary in a narrow range, endowing their frameworks with a high structural distortion and a relatively strong structural rigidity. The present study not only extends SCN−-bridged 3D molecular perovskites to enrich the perovskite family, but also paves a way for the rational design of new molecular perovskites. [ABSTRACT FROM AUTHOR]

Herein, the reaction of (1‐methyl‐1 H‐benzo[d]imidazol‐2‐yl)methanamine (L1) with Co(H2O)6Cl2, in CH3CN at 120 °C, leading to the 2,3,5,6‐tetrakis(1‐methyl‐1 H‐benzo[d]imidazol‐2‐yl)pyrazine (3), isolated as a dimeric cluster {[CoII2(3)Cl4]⋅2 CH3CN} (2), is reported. When O2 and H2O are present, (1‐methyl‐1 H‐benzo[d]imidazole‐2‐carbonyl)amide (HL1′) is first formed and crystallized as [CoIII(L1)2(L1′)]Cl2⋅2 H2O (4) before fusion of HL1′ with L1, giving 1‐methyl‐N‐(1‐methyl‐1 H‐benzo[d]imidazol‐2‐carbonyl)‐1 H‐benzo[d]imidazol‐2‐carboxamide (HL2′′) forming a one‐dimensional (1D) chain of [CoII3(L2′′)2Cl4]n (5). The combination of crystallography and mass spectrometry (ESI‐MS) of isolated crystals and the solutions taken from the reaction as a function time reveal seven intermediate steps leading to 2, but six steps for 5, for which a different sequence takes place. Control and isotope labeling experiments confirm the two carbonyl oxygen atoms in 5 originate from both air and water. The dependence on the metals, compared with FeCl3⋅6 H2O leading to a stable triheteroarylmethyl radical, is quite astounding, which could be attributed to the different oxidation states of the metals and coordination modes confirmed by DFT calculations. This metal and valence dependent process is a very useful way for selectively obtaining these large molecules, which are unachievable by common organic synthesis. [ABSTRACT FROM AUTHOR]

• The experimentally proposed position of proton is proved to be not correct. • L6 backbone is more likely to exist in L6+ form instead of radical. • Systematically g tensors calculations for L6 / HL6+ show experimental EPR result is questionable. • L6·HCl·3CH 3 OH crystal reassigned as L6+·Cl−·3CH 3 OH. • Balanced hole/electron reorganization energy/mobility make L6 good ambipolar semiconductor. L6·HCl·3CH 3 OH crystal was assigned as HL6+·Cl−·3CH 3 OH. Calculations on radical L6 , oxidized cation L6+ , reduced anion L6− , and protonated radical HL6+ favour a L6+ nature rather than HL6+. Spin and charge distributions of L6+ explain its stability. Calculated g tensors for L6 and HL6+ of g ⊥ = 2.0031 and g // = 2.0024 correspond well with other carbon radicals such as methyl radical (2.0025). The much larger experimental g tensors of 2.0130 and 2.0105 are questionable. L6 is predicted to be good ambipolar semiconductor with balanced hole and electron mobilities showing potential applications as OLED and solar cell. [ABSTRACT FROM AUTHOR]

The significant structure transformations, including crystal-to-crystal, crystal-to-solid structure transformation and post-synthetic modification of MOFs, have great pushed MOFs from traditional coordination polymers to be new-generation of molecule based functional materials [[9]]. We deem the structure transformation of MOFs under external stimuli can move on one step further to address a pressing question of "Is there a general strategy to create glasses from MOFs without the need of melting"? Considering the structural similarity of the perturbative MOFs to amorphous organic polymers, direct glass transition may occur under mild temperature below decomposition or melting of the MOFs. [Extracted from the article]

A new series of luminescent phosphine copper(I) complexes with cyano- and hydroxyl-substituted 2,2′-bipyridine ligands [CuI(bpy(CN)2)(P(PhX)3)2](ClO4) [X = H (1); Me (2); Cl (3)], [CuI(bpy(CN)2)(POP)](ClO4) (4), [CuI(bpy(OH)2)(PPh3)2](ClO4) (5) and [CuI(bpy(OH)2)(POP)](ClO4) (6) have been synthesized and characterized. Three of these complexes have been structurally characterized by using X-ray crystallography. The effect of the attaching –CN and –OH groups at the ortho-positions of bpy ligand was investigated. In CH2Cl2 solution, these complexes show yellow to orange phosphorescence, with the emission maxima not only sensitive to the electronic nature of the bipyridine ligands, but also considerably varied with the modification of phosphine ligands. In addition, these complexes show intense tunable green to yellow emissions in their solid state. To elucidate the electronic structures and transitions of these complexes, density functional theory (DFT) calculations on representative examples revealed that the lowest energy electronic transition associated with these complexes predominantly originates from metal-to-ligand charge transfer transitions (MLCT). [ABSTRACT FROM AUTHOR]

The in situ tracking of the pyrolysis of a binary molecular cluster [Zn7(μ3‐CH3O)6(L)6][ZnLCl2]2 is presented with one brucite disk and two mononuclear fragments (L=mmimp: 2‐methoxy‐6‐((methylimino)‐methyl)phenolate) to porous carbon using TG‐MS from 30 to 900 °C. Following up the spilled gas product during the decomposed reaction of zinc cluster along the temperature rising, and in conjunction with XRD, SEM, BET and other materials characterization, where three key steps were observed: 1) cleavage of the bulky external ligand; 2) reduction of ZnO and 3) volatilization of Zn. The real‐time‐dependent phase‐sequential evolution of the remaining products and the processing of pore forming template transformation are proposed simultaneously. The porous carbon structure featuring a uniform nano‐sized pore distribution synthesized at 900 °C with the highest surface area of 1644 m2 g−1 and pore volume of 0.926 cm3 g−1 exhibits the best known capacitance of 662 F g−1 at 0.5 A g−1. [ABSTRACT FROM AUTHOR]

The in situ tracking of the pyrolysis of a binary molecular cluster [Zn7(μ3‐CH3O)6(L)6][ZnLCl2]2 is presented with one brucite disk and two mononuclear fragments (L=mmimp: 2‐methoxy‐6‐((methylimino)‐methyl)phenolate) to porous carbon using TG‐MS from 30 to 900 °C. Following up the spilled gas product during the decomposed reaction of zinc cluster along the temperature rising, and in conjunction with XRD, SEM, BET and other materials characterization, where three key steps were observed: 1) cleavage of the bulky external ligand; 2) reduction of ZnO and 3) volatilization of Zn. The real‐time‐dependent phase‐sequential evolution of the remaining products and the processing of pore forming template transformation are proposed simultaneously. The porous carbon structure featuring a uniform nano‐sized pore distribution synthesized at 900 °C with the highest surface area of 1644 m2 g−1 and pore volume of 0.926 cm3 g−1 exhibits the best known capacitance of 662 F g−1 at 0.5 A g−1. [ABSTRACT FROM AUTHOR]

• Highly diastereoselective synthesis of molecualr rotor from molecualr motor. • First example of TGA on molecular motor. • Non-equilibrium vs equilibrium operation of molecular machines. Developing stereoselective synthetic method is very important to access chiral molecular devices. We herein demonstrate how a proton initiated stereoselective enamine-imine tautomerization converts a molecular motor into a simple rotor with high diastereoselectivity (>20:1 dr). NMR and X-ray crystallography were used to elucidate the structures of both the motor and rotor unambiguously. The activated motion of the rotor about its central single bond was studied from variable temperature NMR (293–423 K) and DFT calculations provide evidence of the origin of diastereoselectivity of enamine-imine tautomerization as well as the rotor dynamics with barrier as high as 39.3 kcal/mol. Results from our work may benefit future design towards stereocontrolled and adaptive molecular machines. [ABSTRACT FROM AUTHOR]

A regio- and stereoselective iodolactonization of internal electron-deficient olefinic acids has been reported, which provides a straightforward access to a series of multi-functionalized seven-membered lactones containing two consecutive chiral centers. The ester substituents on the olefins played a key role in achieving high regioselectivity. This result was proved through experiments and DFT calculations. [ABSTRACT FROM AUTHOR]

We prepared five diarylethenes containing 2-aryl-imidazole as the ethene bridge (L1–L5), and introduced response sites in imidazole rather than in the traditional appended aryl units to regulate their photochromism and thermal stability under acid stimulus. The results show that we can change the thermal stability from P- to T-type, and prevent their photoactivity by acidification, and it is clarified that the stronger the acid or the more acid added, the faster the decay rate of the diarylethene photostability. Furthermore, the prohibited photoactivity could be restored by neutralization with an equimolar amount of base. [ABSTRACT FROM AUTHOR]