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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]

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]

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]

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 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]

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]

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]

An efficient and straightforward synthesis of aryl‐substituted biarylphosphines via unprotected amino acid‐accelerated ruthenium‐catalyzed P‐directed ortho‐C−H arylation reaction is described. This protocol utilized commercial and inexpensive (hetero)aryl chlorides as efficient arylating reagents under solvent‐free reaction conditions. Notably, diverse aryl bromides were also effective for this transformation. With the protocol, a wide variety of mono‐arylated biarylphosphines were obtained in moderate to high yields and excellent selectivity. Moreover, the aryl‐substituted phosphine exhibited higher catalytic performance than its precursor and other substituted phosphines in palladium‐catalyzed Suzuki coupling. [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 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]

Dehydration of (S,S)‐1,2‐bis(1H‐benzo[d]imidazol‐2‐yl)ethane‐1,2‐diol (H4L) to (Z)‐1,2‐bis(1H‐benzo[d]imidazol‐2‐yl)ethenol) (H3L′) was found to be metal‐assisted, occurs under solvothermal conditions (H2O/CH3OH), and leads to [MnII4(H3L)4Cl2]Cl2⋅5 H2O⋅5 CH3OH (Mn4L4) and [MnII4(H2L′)6(μ3‐OH)]Cl⋅4 CH3OH⋅H2O (Mn4L′6), respectively. Their structures were determined by single‐crystal XRD. Extensive ESI‐MS studies on solutions and solids of the reaction led to the proposal consisting of an initial stepwise assembly of Mn4L4 from the reactants via [MnL] and [Mn2L2] below 80 °C, and then disassembly to [MnL] and [MnL2] followed by ligand modification before reassembly to Mn4L′6 via [MnL′], [MnL′2], and [Mn2L′3] with increasing solvothermal temperature up to 140 °C. Identification of intermediates [Mn4LxL′6−x] (x=5, 4, 3, 2, 1) in the process further suggested an assembly/disassembly/in situ reaction/reassembly transformation mechanism. These results not only reveal that multiple phase transformations are possible even though they were not realized in the crystalline state, but also help to better understand the complex transformation process between coordination clusters during "black‐box" reactions. [ABSTRACT FROM AUTHOR]

For ethene derivatives with large groups the cis‐isomer is often quite unstable and unavailable. Herein, we report an exception of two stable coordination complexes, (cis‐L)ZnCl2, starting from trans‐1,2‐bis(1‐R‐benzo[d]imidazol‐2‐yl)ethene (R=H, L1; R=CH3, L2) ligands under solvothermal condition (T ≥140 °C). Using the intensity of the absorption and luminescence spectra as probes we proposed its progressive cis‐to‐trans reversal upon irradiation with UV light, which was confirmed by powder X‐ray diffraction (PXRD). Similar results observed in the series of (cis‐L2)MIICl2 [M=Fe (4), Co (5), Ni (6)] demonstrate the universal strategy. The results of PXRD, NMR spectroscopy, ESI‐MS and DFT calculations support the above conclusion. NMR spectroscopy indicates that irradiation of 1 converts an optimized 71 % of the cis‐isomer to trans, whereas the free trans‐L1 ligand transforms to only 15 % cis‐isomer under similar conditions. Switch controller: Thermal treatment at 140 °C of trans‐L in the presence of MIICl2 (M=Fe, Co, Ni, Zn) led to stable (cis‐L)MCl2 and photoexcitation of the latter caused its transformation back to (trans‐L)MCl2(solvent). The kinetics can be followed by using UV/Vis absorption and luminescence. The results were confirmed by ESI‐MS, NMR spectroscopy, powder X‐ray diffraction and DFT calculations. [ABSTRACT FROM AUTHOR]

A new free carbon radical was obtained in a microwave‐assisted solvothermal reaction of the primary amine (1‐methyl‐1H‐benzo[d]imidazol‐2‐yl)methanamine with FeCl3⋅6 H2O in methanol at 140 °C. Through a combination of crystallography and electrospray ionization mass spectrometry, the reaction process was studied. The longest domino reaction includes 14 steps and forms up to 12 new covalent bonds (9 C−N and 3 C−C bonds) and 3 five‐membered heterocycles. For the first time, the homolytic cleavage of a C−O bond was used to synthesize a triarylmethyl radical. A free carbon radical was obtained in a domino reaction of a primary amine with FeCl3⋅6 H2O in methanol under solvothermal conditions. In this process, which was studied by crystallography and ESI mass spectrometry, the longest domino reaction features 14 steps, and methanol is sequentially activated; in addition, the homolytic cleavage of a C−O bond is proposed. [ABSTRACT FROM AUTHOR]

Two zinc clusters Zn4(H3L)4(NO3)4⋅5H2O (Zn4, H4L=(1,2‐bis(1H‐benzo[d]imidazol‐2‐yl)ethane‐1,2‐diol) and [Zn5(H2L′)6](NO3)4]⋅8H2O⋅2CH3OH (Zn5, H3L′=(1,2‐bis(benzo[d] imidazol‐2‐yl)‐ethenol) have been obtained by the reaction of Zn(NO3)2⋅6H2O with H4L at 80 °C or 140 °C under solvothermal condition. Powder X‐ray Diffraction (PXRD) of precipitate and Electrospray Ionization Mass Spectrometry (ESI‐MS) of reaction solution revealed the existence of transformation behavior from Zn4 to Zn5 by increasing the temperature from 80 °C to 140 °C, or directly heating Zn4 at 140 °C via solvothermal reaction. Here we proposed a possible mechanism involves split process of Zn4 and reassembly to form Zn5. ESI‐MS for single crystals revealed [Zn4(H3L)4−3H]+ splits to [Zn(H3L)]+ via [Zn2(H3L)2−H]+. Time dependent ESI‐MS of reaction solution revealed the [Zn(H2L′)]+→[Zn2(H2L′)2−H]+→[Zn5(H2L′)6−H]3+ stepwise assembly. It also has been captured the in situ reaction mainly occurs in the step of [Zn(H3L)]+ to [Zn(H2L′)]+. [ABSTRACT FROM AUTHOR]

Abstract: Two heptanuclear discs, [Co7(L1)6(CH3O)6]2+ (Co7‐L1) and [Co7(L2)12](ClO4)2 (Co7‐L2), have been prepared by the reaction of [Co(H2O)6](ClO4)2 with Schiff base HL1 (HL1=2‐methoxy‐6‐[(methylimino)methyl]phenolate) or benzimidazole derivative HL2 (HL2=(1H‐benzo[d]imidazol‐2‐yl)methanolate), respectively, at room temperature. In contrast, the reaction of [Co(H2O)6](ClO4)2 with a mixture of the two ligands, having similar coordination ability but different shapes, resulted in the butterfly‐structured tetranuclear cobalt cluster [Co4(L1)2(L2)4](ClO4)2⋅2H2O (Co4). Electrospray ionization mass spectrometry (ESI‐MS) analysis in real time revealed the {Co1}→{Co2}→{Co4}→{Co7} stepwise assembly when a single ligand was employed, but when both ligands were used only {Co4} was obtained, an intermediate of the former reactions. Interestingly, ligand competition was evidenced in the assembly process of the reaction with two ligands; for example, [Co4(L1)4(L2)2]2+ and [Co4(L1)3(L2)3]2+ were the primary clusters observed at the beginning of the reaction, but [Co4(L1)2(L2)4]2+ was the final product. This observation suggests ligand exchange is taking place, and DFT calculations confirmed that these transformations were possible. By varying the ratio of ligands, the abundance of a certain species in the competitive reaction could be controlled. [ABSTRACT FROM AUTHOR]

The bond order and packing ratios in the single-crystal of the two structural polymorphs as well as the detailed electronic structures of the molecular model were studied using density functional theory. The strength of different Mn coordination bonds was analyzed in detail through Mayer bond order. Besides bond length, many other factors such as the orientation of ligand and nature of metal also significantly influence the bond order. Packing ratios calculated using cluster model reveals that packing along b direction in Dimer is more favorable than other directions due to the associated interactions of π-π and Cl...H when packing in this direction. Electronic structure helps explain the formation of Dimer from monomer or direct forming of Chain from ligand/Cl and metal. This would shed light on further understanding the importance of supramolecular interaction on crystal engineering. [ABSTRACT FROM AUTHOR]

The square-planar monomer NiL2 ( Ni1), L=2-ethoxy-6-( N-methyl-iminomethyl)phenolate, reacts with M(H2O)6(ClO4)2, M=Ni or Co, to form heptanuclear disks [Co xNi7− x(OH)6(L)6](ClO4)2 ⋅2 CH3CN ( Co x Ni7− x, x=0-7) and the co-crystal [Co xNi7− x(OH)6L6][NiL2](ClO4)2 ⋅2 CH3CN ( Co x Ni7− x -Ni1) under ambient conditions. It has proved possible to explore the bottom-up assembly process of Co x Ni7− x and Co x Ni7− x -Ni1 in real time. The final products have been characterized by thermogravimetric analysis, IR, elemental analysis, ICP-MS, and single-crystal X-ray diffraction. Time-dependent mass spectrometry (MS) revealed the following reaction steps: Ni1→[M2L3]+→[M4(OH)2L4]2+→[M7(OH)6L6]2+. In contrast, the reaction of Ni1 with Zn2+ only reaches halfway, and crystallographic evidence indicates a butterfly structure for [Zn2Ni2(OH)2Cl2] ( Zn2Ni2), an intermediate that is difficult to isolate in the above Ni-Co series. A summation method has been used to analyze the MS of bimetallic clusters with very similar atomic masses, as is the case for Co and Ni. The results provide ample information on the distribution of Co and Ni within each cluster and their statistical distribution within selected crystals. [ABSTRACT FROM AUTHOR]

Two polymorphs of supramolecular isomers, a discrete dimer and a zig-zag chain, having the same chemical composition, [Mn(Hbit)Cl2] (Hbit=1-methyl-2-(1H-1,2,3-triazol-4-yl)-1H-benzo[d]imidazole), were obtained solvothermally in a one-pot synthesis. The isomers differ in a number of ways: orange blocks versus pale-yellow needles, triclinic P1 versus orthorhombic Pbcn, double µ2-Cl versus alternate single and triple µ2-Cl, coordination number 5 versus 6, and antiparallel versus parallel near-neighbor orientation of Hbit. The packing in each case is driven by the supramolecular interactions, H-bonds (N--H…Cl, C--H…Cl) and π…π overlaps, calculated to be in the range 20-36 kcalmol-1. Calculations gave a difference of only 2 kcalmol-1 in favor of the dimer, which confirms with the observation of principally the dimer at short reaction time. ESI-MS spectra of the dissolved crystals reveal the same fragments with similar distributions. The presence of two fragments at m/z 286.96 [MnIV(Hbit)Cl-2H]+ and 323.94 [MnIII (Hbit)Cl2]+ indicates that [Mn(Hbit)Cl2] is the building unit in both cases; thus, the different orientations of the ligands lead to the two polymorphs stabilized by the respective supramolecular interactions. Importantly, the chain form represents the first example with alternate single and triple µ2-Cl bridges. The magnetic interactions are weakly antiferromagnetic in both cases, with J in the range 0.07-0.34 cm-1; however, high-field EPR analysis reveals moderate magneto-anisotropy with D=0.26(1) cm-1, E=0.06(1) cm-1 and D=0.17(1) cm-1, E=0.03(1) cm-1, respectively. [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]

A series of highly connected metal-organic frameworks (MOFs), [Co8(O)(OH)4(H2O)4(ina)8](NO3)2 ⋅2 C2H5OH ⋅4 H2O ( 1), [Co8(O)(OH)4(H2O)4(pba)8](NO3)2 ⋅8 C2H5OH ⋅28 H2O ( 2), and [Co8(O)(OH)4(H2O)4(pbba)8](NO3)2 ⋅guest ( 3), in which ina=isonicotinate, pba=4-pyridylbenzoate, and pbba=4-(pyridine-4-yl)phenylbenzoate, is reported. These MOFs contain a new secondary building unit (SBU), with a square Co4(μ4-O) central unit having the rare μ4-O2− motif, which is decorated by the other four peripheral cobalt atoms through μ3-OH in a windmill-like shape. This SBU holds 16 divergent connecting organic ligands, pyridyl-carboxylates, to form three different frameworks. The high porosity of desolvated 2 is shown by the efficient gas absorption of N2, CO2, CH4, and H2. In addition, 1 and 2 exhibit unusual canted antiferromagnetic behavior with spin-glass-like relaxation, with blocking temperatures that are fairly high, 20 K ( 1) and 10 K ( 2), for cobalt materials. The relationship between the metal clusters and linkers has been studied, in which the size and rotational degrees of freedom of the ligands are found to control the topology, gas sorption, and magnetic properties. [ABSTRACT FROM AUTHOR]

Cooperative effect: This cover artwork is inspired by the ancient Chinese myth of "King Yi Shooting Down Nine Suns". In the picture, bamboo represents the trans‐isomer of the ligand. After chelation of metallic ions with trans‐ligands under solvothermal condition, a cis‐LMIICl2 could be formed. Similarly, a bow, which stands for the cis‐LMIICl2, is made from pieces of bamboo and rope under hot temperatures. Just as the spectra discrepancy between cis‐LMIICl2 and trans‐isomer is sharply magnified, the bow can send arrows far away, as the legend goes, even to shoot the other nine suns down. More information can be found in the Full Paper by H.‐B. Xu, M.‐H. Zeng, et al. on page 5177. [ABSTRACT FROM AUTHOR]

Domino Reactions. In their Communication on page 3748 ff., M.‐H. Zeng et al. describe the synthesis of a free carbon radical through the domino reaction of a primary amine with FeCl3⋅6 H2O in methanol under solvothermal conditions. [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]

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]

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]

In the title compound, C16H11NO3, the quinolin-8-yl­oxy and 2-carboxy­phenyl groups are linked through an ether O atom, the angle at this atom being 116.4 (1)° in one mol­ecule and 114.8 (1)° in the other independent mol­ecule. In both mol­ecules, the carboxylic acid group inter­acts with the heterocyclic moiety through an intra­molecular hydrogen bond. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, C16H16N4O22+·2NO3−, the cation, which lies on a twofold rotation axis, inter­acts with the nitrate anions, giving rise to a hydrogen-bonded layer structure. [ABSTRACT FROM AUTHOR]

In the title compound, [Cd(C(10)H(16)O(4))(C(16)H(14)N(4))](n), the Cd(II) ion is six-coordinated in a distorted octa-hedral geometry by four carboxyl-ate O atoms from two sebacate ligands and two N atoms from the chelating 1,4-bis-(2-benzimidazol-yl)ethanebutane ligand. Neighboring Cd(II) ions are bridged by the sebacate ligands, forming a zigzag polymeric chain structure. The chains are further extended into a three-dimensional supra-molecular structure through inter-molecular N-H⋯O hydrogen bonds.

In the mononuclear title complex, [Co(NCS)(2)(C(9)H(10)N(2)O)(2)]·CH(3)OH, the cobalt(II) ion is surrounded by two (1-methyl-1H-benzimidazol-2-yl)methanol bidentate ligands and two thio-cyanate ligands, and exhibits a distorted octa-hedral coordination by four N atoms and two O atoms. The structure is consolidated by hydrogen bonds between the organic ligand, thio-cyanate anion and the uncoordinated methanol mol-ecule, leading to a chain along [100].

The title complex, [Mn(N(3))(2)(C(9)H(10)N(2)O)(2)], possesses crystallographically imposed twofold symmetry. The Mn(II) atom is coordinated by four N atoms and two O atoms in a distorted octa-hedral geometry. The crystal packing is stabilized by strong inter-molecular O-H⋯N hydrogen bonds.

The title compound, [ZnCl(2)(C(16)H(14)N(4))], crystallizes with two mol-ecules in the asymmetric unit. The Zn(II) atoms show distorted tetrahedral coordination environments. Adjacent mol-ecules are linked by N-H⋯Cl hydrogen bonds, forming a three-dimensional network.

In the crystal structure of the title coordination polymer/co-crystal, {[ZnCl(2)(C(18)H(18)N(4))]·C(18)H(18)N(4)}(n), the tetrahedrally coordinated Zn(II) ions are linked by the N-heterocycle into a linear chain. Another N-heterocycle present is not coordinated to the metal atom but inter-acts with the chain through N-H⋯N and N-H⋯Cl hydrogen bonds. The butyl chain of the uncoordinated ligand is disordered over three positions in a 0.511 (4):0.289 (5):0.200 (5) ratio.