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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]

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]

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]

Background: Coffin-Siris syndrome (CSS) is a rare autosomal dominant disorder characterized by intellectual disability, developmental delay, and characteristic facial features. Few patients with cutaneous phenotype in this rare syndrome have been reported.Case Presentation: Herein, we describe a 12-year-old Chinese girl diagnosed with CSS, who was referred to our hospital because of intellectual disability and short stature. Prominent characteristics of the cutaneous system were observed: (1) A congenital giant nevus from the left frontal and temporal regions to the entire left scalp; and (2) multiple melanocytic nevi on the face and trunk. Whole exome sequencing revealed a novel heterozygous variant in the ARID1B gene. Recombinant human growth hormone (rhGH) was given for short stature, and resulted in significantly improved height. No enlargement or malignant transformation of nevi occurred within 4 years of follow-up.Conclusion: The symptoms in cutaneous system is noteworthy,which may be a neglected phenotype in CSS.The therapeutic response of growth hormone is effective in this patient and no tumor related signs were found. [ABSTRACT FROM AUTHOR]

(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]

Different surface planes of various types of titanium dioxide (TiO2) crystals have diverse catalysis effects on the splitting of H2O and H2 and the electronic structures of the formed hydroxylated TiO2 vary significantly. A series of sixteen types of hydroxylated TiO2 surfaces containing two types of hydroxyls (OH1 and OH2) on four kinds of low index surfaces [(001), (100), (101), and (110)] of two types of crystals [anatase (A) and rutile (R)] are studied using first-principles density functional theory calculations. The catalyzed splitting of H2O and H2 on the eight low index surfaces is compared using Gibbs free energy. The geometries and electronic structures including the total and partial density of states and the charge density distribution of the sixteen hydroxylated surfaces are systematically described. The electronic structures of R-101, R-001, A-110, A-100, and A-001 surfaces are more significantly influenced by hydroxylation than other surfaces and the effects of OH2 are larger than those of OH1. In particular, the band gap values decrease and a new electronic energy state appears in R-001-OH2 and A-100-OH2. A new electronic state appears in the middle of the bands of R-101 and A-110 surfaces upon hydroxylation. The electron spin balance at the edge of the conduction band minimum of A-001-OH2 is disturbed. This research can provide theoretical guidance for experimental researchers to design surface hydroxylated TiO2 materials with tunable electronic structures and high catalytic performance. [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 goal of material chemistry is to study the relationship among hierarchical structure, chemical reaction and precision preparation for materials, yet tracking pyrolysis process on multi-dimensional scale is still at primary stage. Here we propose packing mode analysis to understand evolution process in high temperature reaction. As a proof of concept, we first design a salan-ligated Mn3 (Mn3(3-MeOsalophen)2(Cl)2) cluster and pyrolyze it under an inert atmosphere directly to a mixed valence MnOx embedded in a porous N-doped carbon skeleton (MnOx/C). Meanwhile, combining thermogravimetry-mass spectrometry (TG-MS) with other characterization techniques, its pyrolysis process is precisely tracked real-time and Mn2+/Mn3+ ratios in the resulting materials are deduced, ensuring excellent electrochemical advantages. As a result, the as-preferred MnOx/C-900 sample reaches 943 F/g at 1 A/g, maintaining good durability under 5,000 cycles with 90% retention. The highlight of packing mode analysis strategy in this work would provide a favorable approach to explore the potential relationship between structure and performance in the future. [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]

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]

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]

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]

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]

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]

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]

Analyses of the structural information of molecular fragments from the mass spectra of the solid-state products and their reaction solutions allow for the understanding of their formation and of their diverse properties. The reaction of CuCl2 and (1-methyl-1H-benzo[d]imidazole-2-yl)methanol (HL) led only to crystals containing molecular dimers of [Cu2(L)2Cl2] (Cu2). The CuII–CuII distance and Cu–OR–Cu angle in the structure are 3.044 Å and 104.8°, respectively. The magnetic susceptibility (3–400 K) is characterized by a very strong intradimer antiferromagnetic interaction of J = −465 and interdimer zj = −0.83 cm−1. But mass spectrometry of a dissolved single crystal in different source energies identifies both its fragmentation and oligomerization to [Cu II3 ] and [Cu II4 ]. DFT calculations give the relative stabilization energies of the fragments observed in ESI-MS to provide a formation process. [ABSTRACT FROM AUTHOR]

A tandem reaction of pyridin-2-ylmethanamine (L1′) with 8-hydroxyquinoline-2-carbaldehyde (HL1) assisted by FeCl3 was observed to give the new nitrogen heterocycle HL3 (HL3=2-(imidazo[1,5-a]pyridin-3-yl)quinolin-8-ol) as its Fe(III) complex, [Fe(L3)Cl2] (Fel). Electrospray ionization mass spectrometry (ESI-MS) reveals its formation involves three steps: (1) coordination of both HL1 and Ll′ to Fe, (2) aldehyde-amine coupling, and (3) ring closure. The results of electronic absorption spectroscopy, cyclic voltammetry, and density functional theory (DFT) calculations show the proximity of the optical transition energy to that of the excitation of 3O2 to 1O2, which prompted us to explore its application as a photosensitizer for photodynamic therapy (PDT). Photo-toxicity studies show that Fel exhibits the highest anti-proliferation efficiency in human breast cancer MDA-MB-231 cells under light irradiation. Moreover, studies with orthotopic models of breast cancer further expounded the anti-tumor activity of Fe1 with no significant toxicity to other organs and low retention in the body. [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]

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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]

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]

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 conjugation of bridging bis(diphenylphosphine oxide) alkane or arene ligands was found to control the structural dimensionality and the emission color of complexes from reactions with SmIII(hfac)3(H2O)2 (hfac− = hexafluoroacetylacetonato) while retaining the Sm…Sm distances. Bis(diphenylphosphine oxide)-1,4-butane (L1) affords a one-dimensional (1D) ribbon {Sm(hfac)3(L1)}∞ (1) that emits red color, while bis(diphenyl-phosphinoyl)-1,4-benzene (L2) results in a two-dimensional (2D) network {Sm(hfac)2(CF3COO)(L2)3}∞ (2) and near-white emission, but bis(diphenyl-phosphinoyl)-9,10-anthracene (L3) forms a zero-dimensional (0D) cyclic structure {Sm(hfac)3(L3)}2 (3) with strong π…π interactions that emit green color. Noticeably, the conjugation change is accompanied by a configurational change of coordination from trans for 1 and 2 to cis for 3. The color change is associated with the superposition of ligand and Sm based electronic band energies and their intensities. Such white light emission by a single compound having contributions from different building components is quite rare. [ABSTRACT FROM AUTHOR]

We showed that the simple organic salt bromocholine bromide is a molecular ferroelectric with a moderate ferroelectric phase transition temperature (329 K). The order–disorder dynamic transition of organic cations results in symmetry breaking from the centrosymmetric paraelectric phase (P21/m) to polar ferroelectric phase (P21), affording a moderate spontaneous polarization of 1.0 μC cm−2 for the ferroelectric phase, as well as a switchable SHG signal and pyroelectric property with feasible “on/off” contrasts. [ABSTRACT FROM AUTHOR]

The newly synthesized ionic triple salt Ru–Er, {[RuII(bpy)2(dbim)][ErIII(hfac)4][CF3COO]·H2O} (bpy = 2,2′-bipyridine; hfac− = hexafluoroacetylacetonate; dbim = 2,2′-dibenzimidazole) exhibits near-infrared (NIR) emission at 1535 nm by intermolecular Ru → Er (d → f) energy transfer across supramolecular interactions when pumped within the Ru(ii) 3MLCT band. It is the first such observation for a transition metal–lanthanide ionic pair. [ABSTRACT FROM AUTHOR]