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Two {Cu2I2} cluster-bearing metal organic frameworks (MOFs) of {[Eu(CuI)2(INA)3DMF]·0.95DMF}n (Eu-CuI-INA) and {K[(CH3)2NH2]Sr4(INA)2(DMF)2{(Cu2I2)2(INA)8}·2H2O}n (Sr-K-CuI-INA, HINA = isonicotinic acid, DMF = N,N-dimethyl formamide) were prepared and characterized in this work. Both materials feature a three-dimensional (3-D) structure, in which the {Cu2I2} clusters and Eu3+ (or Sr2+) metal ions are coordinated by INA− ligands with pyridine and carboxylic groups, respectively. Impressively, Sr-K-CuI-INA exhibits sensitive fluorescence sensing behaviors towards cysteine and nitro-bearing molecules, demonstrating potential FL sensing applications for bio and explosive molecules. This work would provide a good reference for designing fluorescent MOF probes containing CuI molecules. [ABSTRACT FROM AUTHOR]

Pore size tunability is of great importance to porous materials with applications in sieving adsorption, barrier separation, stereospecific catalysis, and so forth. In this work, we present three calcium based metal organic frameworks (Ca-MOFs) with tunable pore sizes. The title Ca-MOFs of [Ca6(tatb)4(H2O)(amide)4] (H3tatb = 4,4′,4′′-(1,3,5-triazine-2,4,6-triyl)tribenzoic acid, amide = dimethylformamide (DMF) for 1, dimethylacetamide (DMA) for 2, and formyldiethylamine (DEF) for 3, respectively) featuring three dimensional (3D) structures were constructed from inorganic 1D rod-like secondary building units (SBUs) of [Ca(COO)4(amide)]n and the organic linker of H3tatb. Interestingly, by altering the terminal coordinated amides with alkyl groups extended into the 1D pores, the pore sizes of title compounds could be finely regulated. As a result, these compounds exhibited pore size dependent fluorescence sensing behavior towards trinitrophenol (TNP), a classic explosive molecule. Different from that in previous studies, this work strategically employs terminal coordinated amides, which typically get removed to create porosity, to tune the pore sizes of the resultant Ca-MOFs, providing a convenient way to modify the pore structures of porous materials. [ABSTRACT FROM AUTHOR]

The search for laser-ignitable energetic materials catering to the safety and accuracy requirements in military and civilian affairs is an important yet challenging task. In this work, non-explosive and stable nitro bearing ligands of 3,5-dinitro-4-chlorobenzoic acid (HDNB-Cl) and 3,5-dinitro-4-hydroxybenzoic acid (HDNB-OH) have been adopted as energetic modules and organic building units to assemble with copper ions to construct energetic coordination complexes. The d–d transition introduced by Cu2+ endows the as-synthesized compounds to display remarkable absorptions of NIR light, and thus achieve efficient photothermal conversions upon irradiation by an 808 nm laser. As a result, the DNB-Cl based complexes can be laser-ignited and strong deflagration has been observed. The satisfactory thermal stability and tolerance toward friction and electrostatic discharge make them good candidates as laser-ignitable energetic materials. Unlike the conventional energetic materials based on nitrogen-rich organics (e.g., azido, furazan, and heterocyclic compounds), this work reveals that the easily functionalized nitro-bearing carboxylate ligand is an alternative energy module for assembling stable energetic complexes, and the coordination interaction-induced photothermal conversion would be an efficient strategy to achieve laser ignition for the resultant energetic compounds. [ABSTRACT FROM AUTHOR]

Developing efficient adsorbent materials towards energy gas purification, e.g. CO2 removal from natural gas or hydrocarbon separation, is an important but extremely challenging task. Herein, taking advantage of a cationic bipyridinium ligand in competition with a multicarboxylate ligand for binding with metal ions, a porous material with open carboxylate oxygen atoms exposed on the pore surface has been demonstrated as an efficient adsorbent for gas separation. The polar environment arising from the cationic pyridinium moiety and the negative carboxylate group endows the title compound with selective affinity to CO2 over CH4. Moreover, the rich open O donor sites on the channel surface enable the resultant coordination polymer to selectively adsorb C2H2 over C2H4 through H-bonding interactions. The separation mechanism has been revealed by theoretical studies. This work provides a specific guidance for the design of applicable porous materials toward energy resource purification. [ABSTRACT FROM AUTHOR]

Photoinduced bending behavior triggered by [2 + 2] cycloaddition of a photoactive complex has been successfully achieved, accompanied by photochromic and fluorescence changes that provide convenience for long-distance observation of photomechanical motion. The key design feature is based on the introduction of flexible methylene groups and cation–π interactions. Moreover, the potential application in photomechanical devices was reflected by bending and supporting force experiments on the complex composite film, which is of increasing importance especially in soft actuators and robots. [ABSTRACT FROM AUTHOR]

N-Heterobiaryls are common skeletons found in biological molecules, pharmaceuticals and ligands. Herein, we document an efficient and redox-neutral photocatalytic system to obtain functionalized N-heterobiaryls under mild conditions. Substrates bearing variegated functional groups are compatible with the developed photocatalytic conditions. This method is translatable to gram-scale synthesis, with a photocatalyst loading as low as 0.1 mol% and minimal variation of the yield. The starting materials are commercially available, demonstrating the practicality and accessibility of this methodology. Interestingly, phenols can serve both as coupling partners and proton donors. Arenes without a phenolic hydroxyl group also underwent efficient coupling with HFIP as a solvent. [ABSTRACT FROM AUTHOR]

N-Aryl phenothiazines and phenoxazines are of significant importance in various disciplines throughout academia and industry. The conventional synthetic strategy for the construction of these structures centers on the transition-metal-catalyzed cross-coupling of aryl halides with phenothiazines or phenoxazines. Here we present an organocatalytic approach to access N-naphthyl phenothiazine and phenoxazine scaffolds through a straightforward C–H amination of arenes as enabled by an azo group. This reaction features operational simplicity, adequate substrate generality and excellent functional group compatibility. Notably, the efficiency of the catalyst could be perfectly preserved after 5 catalytic cycles. [ABSTRACT FROM AUTHOR]

Herein, two indium-based metal organic frameworks (In-MOFs), namely [(CH3)2NH2][In(bpdc)2]·(DMF)2 (1) and [(CH3)2NH2]3[(In3Cl2)(bpdc)5]·(H2O)5(DMF)2.5 (2, bpdcH2 = 4,4′-biphenyldicarboxylic acid), have been synthesized and characterized. By introducing a Cl− ion as a terminal ligand to break the symmetrical coordination environment of a typical InO8 dodecahedron as that in a three dimensional (3D) compound 1 with a 4-connected and four-fold interpenetrating dia net topology, a chiral 2D compound 2 with unique double-helical chains along the c axis is generated. Fluorescence (FL) measurements indicate that both compounds demonstrate excellent FL sensing behaviour towards CS2, a trace amount of Fe3+ ions and nitro-containing explosives. Notably, the layered 2 exhibits a unique “turn on” FL sensing behaviour towards thiol molecules, e.g., cysteine and 1-butylmercaptan, by exfoliating 2 into a few-layer FL material. The detection mechanism was investigated in detail by multiple characterizations including but not limited to EDS, SEM and AFM. The [(CH3)2NH2]+ cations in 2 can be replaced by an Eu3+ ion to generate 2@Eu3+ which exhibits a new characteristic sharp red emission of Eu3+. More importantly, 2@Eu3+ can serve as a convenient ratiometric FL sensor for temperature, demonstrating obvious color changes from weak purple to red under UV light as the temperature increases. Furthermore, cationic green- and red-light emitting dyes incorporated with 2@dyes emit white light with 17.28% quantum yield. [ABSTRACT FROM AUTHOR]

Thiol molecules play a crucial role in natural and physiological systems. Thus, the exploration of efficient fluorescent (FL) probes for thiols is highly demanded. Here, we demonstrate that the ratiometric FL detection of thiols can be achieved using a CuI modified FL-Mg-coordination polymer (CP) formulated as [Mg2(1,4-NDC)2(H2O)2](bpy)(H2O)4 (1,4-NDCH2 = 1,4-naphthalene dicarboxylic acid, bpy = 4,4′-dipyridyl). This FL composite (1-CuI) shows dual emission generated from the host framework of Mg-CP and CuI–bpy interactions. Due to the strong coordination interaction between the sulfhydryl and Cu atom, CuI was “stuck down” by the thiols and the energy transfer between the host framework of Mg-CP and the CuI-bpy moiety was cut off. As a result, the corresponding FL of 1-CuI changes from light green to blue and a reliable ratiometric FL assay for thiols was generated. Moreover, quantitative detection of thiols could be easily realized through measuring the ratio of FL intensity for Mg-CP (I420) to that for CuI-bpy (I535). Notably, due to the channel-confined effect of the Mg-CP, the dual emitting composite exhibited a unique size-selectivity for thiols with different substituent groups. [ABSTRACT FROM AUTHOR]

In this study, a series of strongly luminescent organosilica-modified carbon dots were successfully synthesized in a scalable manner via hydrothermal treatment of citric acid and glucose in the presence of a silane coupling agent. Organosilica as a stable component coupled with the surface of carbons leads to the formation of gel-like materials. The obtained carbon dots can be homogeneously dispersed in various polar solvents such as water or ethanol to produce an optical solution. Importantly, the abundance of organosilica groups on the surface makes carbon dots ideally suited for use as fantastic carbon precursors for the construction of porous carbon materials. The carbons resulting from the pyrolysis of carbon dots consist of interconnected carbon nanoparticles with surface areas of up to 725 m2 g−1 and nitrogen content of 4.84%. Such carbons show potential application as supercapacitor electrodes with high specific capacitance of 185.4 F g−1 at 0.5 A g−1 and 176.3 F g−1 at 1 A g−1 in 6 mol L−1 KOH. Considered a relatively green and simplistic process, this current synthetic protocol would be a promising avenue to access functional carbon materials with tunable porosity, heteroatom doping and specific morphology. [ABSTRACT FROM AUTHOR]

In this paper, we introduced light and abundant metal magnesium into a cobalt-based metal organic framework (Co-MOF, [(CH3)2NH2]2[Co3(bpdc)4]·5DMF·4CH3OH) (1, H2bpdc = 4,4′-biphenyldicarboxylic acid, DMF = N,N-dimethylformamide) as a heteroatom to synthesize Mg–Co bimetallic MOFs, namely [(CH3)2NH2]2[MgCo2(bpdc)4]·4DMF·5CH3OH (2) and [(CH3)2NH2]2[Mg1.2Co1.8(bpdc)4] 4DMF·4CH3OH·6H2O (3). Based on the formation of a rather low density framework after the introduction of the light Mg2+, such bimetallic MOFs exhibited higher gas adsorption abilities than the isostructural Co-based MOF 1. N2 adsorption measurements demonstrate that the BET surface area of 3 is 305.4 m2 g−1, exhibiting three times that of 1 (104.4 m2 g−1). Significantly, due to the introduction of the low-melting Mg2+, the Mg–Co MOFs could be further utilized as precursors for porous carbons only by calcination at a mild temperature of 600 °C which could exhibit a BET surface as high as 712.78 m2 g−1. Furthermore, after post-synthetic modification with a N/S heteroatom at 900 °C, the obtained hierarchical carbons exhibit superior activity in the oxygen reduction reaction (ORR) that is comparative to the commercial Pt/C catalyst. TEM results indicate that Co-embedded carbon nanotube (CNT)-containing hierarchically nanoporous carbons have been obtained. This study may offer a new avenue to prepare porous carbons utilizing Mg-containing bimetallic MOFs as sacrificial templates. [ABSTRACT FROM AUTHOR]

An olefin-containing pyridinium derivative, 1-(4-carboxybenzyl)-4-[2-(4-pyridyl)-vinyl]-pyridinium chloride (HBCbpeCl) has been introduced into a novel 2D metal–organic framework with rare right- and left-handed spiral nanotubular channels arranged alternately in the structure. The 1D channel is modified by positively-charged pyridinium segments, which shows high affinities to Lewis basic molecules such as methanol, ethanol, and water vapor. Additionally, the BCbpe molecules in the structure have been directed through cation–π interactions to be aligned antiparallel to each other with the C=C double bond arranged properly for [2 + 2] photocycloaddition, which can be triggered to undergo structural transformation from 2D to 3D. This post-cycloaddition modification strategy has been used to separate alcohols and water, which includes a successful adjustment of large tailor-made channels by the [2 + 2] cycloaddition reaction. The gas-chromatographic separation experiments show that ethanol can be better separated from water through a column filled with a post-cycloaddition modified sample than the as-synthesized one. [ABSTRACT FROM AUTHOR]

An unprecedented and efficient organic base-catalysed highly chemoselective carbo- and oxytrifluoromethylation of unactivated alkenes with Togni's reagent was developed. The switchable chemoselectivity was tuned by simply changing the organic base catalyst and solvent. Mechanistic studies indicated that a radical cyclization pathway for carbotrifluoromethylation in DMSO and a carbocation pathway for oxytrifluoromethylation in DCE were probably involved. [ABSTRACT FROM AUTHOR]

A new 3D host–guest Mg-CP shows tuneable dual emission and ultimately achieves direct white emission after being post-modified with CuI, which also represents the first photochromic Mg-CP based on a non-photochromic organic linker that exhibits reversible colour changes. [ABSTRACT FROM AUTHOR]

The fabrication of hierarchical porous carbons with super-high surface areas from sustainable biomass is still challenging. Silica nanocasting and KOH activation are amenable to porosity introduction and therefore remain the most crucial pathways for porous carbon synthesis. However, these methods are multistep and rather energy-intensive processes. In the present work, a series of hierarchical porous carbon monoliths were prepared from fructose by a one-step ionothermal carbonization approach using an iron-based ionic liquid as solvent, and a porogenic agent. Importantly, the prepared carbon materials show narrow bi-modal pore distributions and possess super-high surface areas of ca. 1200 m2 g−1, which is the highest value in hydrothermal carbons as far as we know. The morphology of the monolithic carbons consists of interconnected carbon particles with fairly small particle sizes of ca. 30–50 nm. Moreover, the spent ionic liquids could be easily recovered by Soxhlet extraction, at above 98% for the cycle of ionothermal carbonization. Owing to their favorable textural properties, the impact of the porosity of the ionothermal carbons on their electrochemical capacitive performance was investigated. The ionothermal carbons exhibit a high specific capacitance of 245 F g−1 at a current density of 1 A g−1. The promising capacitive performance could be attributed to the high surface areas and well-controlled micro- and mesoporosities of the carbons. In addition, the hierarchical porosity and high surface area of the carbon lend it to highly efficient adsorption of methyl orange (qe = 240 mg g−1) and malachite green (qe = 170 mg g−1) from wastewater. [ABSTRACT FROM AUTHOR]

Two isomorphous halogen-bridged metal–organic frameworks have been solvothermally synthesized based on the bipyridinium ligand and structurally characterized. The two compounds show an eye-detectable color development upon light irradiation, but different coloration degrees. The relationship between the structure and photosensitivity has been studied in detail. The photochromic properties of the bipyridinium unit have been used to modulate the luminescence under light illumination. Compound 1 is the first example showing photo-modulated luminescence switching featuring a non-destructive readout capability based on transition metals. [ABSTRACT FROM AUTHOR]

A multi-stimuli responsive small molecule organic material has been developed, which for the first time exhibits dual-wavelength response to render photocoloration under visible light and turn-on luminescence under UV light. The colored product can be bleached and shows turn-on luminescence again when re-exposed to UV light. [ABSTRACT FROM AUTHOR]

A new magnesium coordination polymer (Mg-CP), namely [Bmim]2[Mg6(NDC)5(HNDC)2(HCOO)2] (1, H2NDC = 1, 4-naphthalenedicarboxylic acid, [Bmim] = 1-butyl-3-methyl-imidazolium ion), has been ionothermally synthesized and structurally characterized. Single-crystal X-ray structural determination indicated that the title compound possessed an anionic three-dimensional (3D) framework constructed by the interconnections of unprecedented hexanuclear magnesium-carboxylate clusters as secondary building units (SBUs) via bridging NDC ligands. Compound 1 exhibited blue luminescence emission at 440 nm when excited at 360 nm. Significantly, the title non-porous Mg-CP could be utilized as a precursor for preparing porous carbons through thermal decomposition in optimized conditions. Different from the reported high decomposition temperature (＞1000 °C) mostly based on porous Zn-CP precursors, the optimum decomposition temperature for 1 was only 700 °C, and the resulting porous carbons showed 465 cm3 g−1 adsorption volume for N2. The as-prepared carbon exhibited finely selective N2 adsorption ability over H2 and CO2. This work may provide a certain guiding significance for exploiting ionothermally synthesized Mg-CPs as a new type of precursor towards porous carbons. [ABSTRACT FROM AUTHOR]

A flexible bipyridinium ligand with Lewis acidic sites has been introduced into two isomorphous metal–organic frameworks to yield luminescent porous materials with subtriangular pore windows, which exhibit sensitive fluorescent response for ammonia molecules and can be proved at the molecular level by Raman spectroscopy. [ABSTRACT FROM AUTHOR]

A photoactive porous metal–organic complex has been constructed based on an olefin-containing pyridinium derivative, 1-(3-carboxybenzyl)-4-[2-(4-pyridyl)-vinyl]-pyridinium chloride (m-HBCbpe·Cl). The double bond in the BCbpe ligand has been successfully aligned in a photoactive orientation through cation–π interactions, thus enabling the complex to undergo a photochemical [2 + 2] cycloaddition reaction in 100% yield upon UV-light irradiation. Sudden cracking of the crystal can be observed during this process. Interestingly, photocycloaddition not only induces fluorescence switching from no luminescence to strong yellow luminescence emission under UV light, but also triggers a structural change which has a significant impact on CO2 adsorption. [ABSTRACT FROM AUTHOR]

Two {Cu 2 I 2 } cluster-bearing metal organic frameworks (MOFs) of {[Eu(CuI) 2 (INA) 3 DMF]·0.95DMF} n (Eu-CuI-INA) and {K[(CH 3 ) 2 NH 2 ]Sr 4 (INA) 2 (DMF) 2 {(Cu 2 I 2 ) 2 (INA) 8 }·2H 2 O} n (Sr-K-CuI-INA, HINA = isonicotinic acid, DMF = N , N -dimethyl formamide) were prepared and characterized in this work. Both materials feature a three-dimensional (3-D) structure, in which the {Cu 2 I 2 } clusters and Eu 3+ (or Sr 2+ ) metal ions are coordinated by INA - ligands with pyridine and carboxylic groups, respectively. Impressively, Sr-K-CuI-INA exhibits sensitive fluorescence sensing behaviors towards cysteine and nitro-bearing molecules, demonstrating potential FL sensing applications for bio and explosive molecules. This work would provide a good reference for designing fluorescent MOF probes containing CuI molecules.

Developing efficient adsorbent materials towards energy gas purification, e.g. CO 2 removal from natural gas or hydrocarbon separation, is an important but extremely challenging task. Herein, taking advantage of a cationic bipyridinium ligand in competition with a multicarboxylate ligand for binding with metal ions, a porous material with open carboxylate oxygen atoms exposed on the pore surface has been demonstrated as an efficient adsorbent for gas separation. The polar environment arising from the cationic pyridinium moiety and the negative carboxylate group endows the title compound with selective affinity to CO 2 over CH 4 . Moreover, the rich open O donor sites on the channel surface enable the resultant coordination polymer to selectively adsorb C 2 H 2 over C 2 H 4 through H-bonding interactions. The separation mechanism has been revealed by theoretical studies. This work provides a specific guidance for the design of applicable porous materials toward energy resource purification.

Photoinduced bending behavior triggered by [2 + 2] cycloaddition of a photoactive complex has been successfully achieved, accompanied by photochromic and fluorescence changes that provide convenience for long-distance observation of photomechanical motion. The key design feature is based on the introduction of flexible methylene groups and cation-π interactions. Moreover, the potential application in photomechanical devices was reflected by bending and supporting force experiments on the complex composite film, which is of increasing importance especially in soft actuators and robots.

Luminescent metal-organic frameworks (LMOFs) with diverse structural features and promising fluorescence-based applications have attracted wide attention in the past two decades. In this work, a LMOF with the formula [Ca 4 (tcbpe-F) 2 (H 2 O) 3 ] (1, LMOF-411) has been constructed from calcium (Ca) and 1,1,2,2-tetrakis(4-(4-carboxyphenyl)phenyl)ethene (H 4 tcbpe-F). Compound 1 features a three-dimensional framework with a 10-nodal net topology. Due to the relatively high hydration energy of Ca 2+ , compound 1 readily transforms into a new phase formulated as [Ca(H 2 tcbpe-F)(H 2 O) 2 ] (1') upon exposure to water. Combining experimental characterization and theoretical calculations, we elucidated the mechanism of H 2 O-induced phase transition from 1 to 1'. Notably, the water induced phase transformation can be detected visibly from the change in luminescence, which originates from the fluorescent linker. Compound 1 emits green light ( λ em = 490 nm) under UV excitation, while compound 1' emits bright yellow light ( λ em = 550 nm) under blue excitation (450 nm). Compound 1' represents the first Ca based LMOF yellow phosphor and its luminescence quantum yield reaches 68%. It can be coated directly onto a commercial blue light-emitting-diode (LED) chip to fabricate a white LED (WLED)., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

N-Phenylphenothiazine as an inexpensive, highly reductive and oxygen tolerant organophotocatalyst has exhibited potential in various challenging photochemical transformations. Here we report a general and straightforward method to access structurally diverse N-phenylphenothiazine derivatives by means of a novel electrochemical tool. The introduction of a 2-naphthylamine moiety with an extended π-system and an amine group led to the variation of spectral characterization. Photochemical verification experiments demonstrated that the formed N-arylation products with good efficacy and chemo/site-control displayed competitive catalytic activity in challenging transformations.

In this study, a series of strongly luminescent organosilica-modified carbon dots were successfully synthesized in a scalable manner via hydrothermal treatment of citric acid and glucose in the presence of a silane coupling agent. Organosilica as a stable component coupled with the surface of carbons leads to the formation of gel-like materials. The obtained carbon dots can be homogeneously dispersed in various polar solvents such as water or ethanol to produce an optical solution. Importantly, the abundance of organosilica groups on the surface makes carbon dots ideally suited for use as fantastic carbon precursors for the construction of porous carbon materials. The carbons resulting from the pyrolysis of carbon dots consist of interconnected carbon nanoparticles with surface areas of up to 725 m2 g-1 and nitrogen content of 4.84%. Such carbons show potential application as supercapacitor electrodes with high specific capacitance of 185.4 F g-1 at 0.5 A g-1 and 176.3 F g-1 at 1 A g-1 in 6 mol L-1 KOH. Considered a relatively green and simplistic process, this current synthetic protocol would be a promising avenue to access functional carbon materials with tunable porosity, heteroatom doping and specific morphology.

In this paper, we introduced light and abundant metal magnesium into a cobalt-based metal organic framework (Co-MOF, [(CH 3 ) 2 NH 2 ] 2 [Co 3 (bpdc) 4 ]·5DMF·4CH 3 OH) (1, H 2 bpdc = 4,4'-biphenyldicarboxylic acid, DMF = N,N-dimethylformamide) as a heteroatom to synthesize Mg-Co bimetallic MOFs, namely [(CH 3 ) 2 NH 2 ] 2 [MgCo 2 (bpdc) 4 ]·4DMF·5CH 3 OH (2) and [(CH 3 ) 2 NH 2 ] 2 [Mg 1.2 Co 1.8 (bpdc) 4 ] 4DMF·4CH 3 OH·6H 2 O (3). Based on the formation of a rather low density framework after the introduction of the light Mg 2+ , such bimetallic MOFs exhibited higher gas adsorption abilities than the isostructural Co-based MOF 1. N 2 adsorption measurements demonstrate that the BET surface area of 3 is 305.4 m 2 g -1 , exhibiting three times that of 1 (104.4 m 2 g -1 ). Significantly, due to the introduction of the low-melting Mg 2+ , the Mg-Co MOFs could be further utilized as precursors for porous carbons only by calcination at a mild temperature of 600 °C which could exhibit a BET surface as high as 712.78 m 2 g -1 . Furthermore, after post-synthetic modification with a N/S heteroatom at 900 °C, the obtained hierarchical carbons exhibit superior activity in the oxygen reduction reaction (ORR) that is comparative to the commercial Pt/C catalyst. TEM results indicate that Co-embedded carbon nanotube (CNT)-containing hierarchically nanoporous carbons have been obtained. This study may offer a new avenue to prepare porous carbons utilizing Mg-containing bimetallic MOFs as sacrificial templates.

An olefin-containing pyridinium derivative, 1-(4-carboxybenzyl)-4-[2-(4-pyridyl)-vinyl]-pyridinium chloride (HBCbpeCl) has been introduced into a novel 2D metal-organic framework with rare right- and left-handed spiral nanotubular channels arranged alternately in the structure. The 1D channel is modified by positively-charged pyridinium segments, which shows high affinities to Lewis basic molecules such as methanol, ethanol, and water vapor. Additionally, the BCbpe molecules in the structure have been directed through cation-π interactions to be aligned antiparallel to each other with the C[double bond, length as m-dash]C double bond arranged properly for [2 + 2] photocycloaddition, which can be triggered to undergo structural transformation from 2D to 3D. This post-cycloaddition modification strategy has been used to separate alcohols and water, which includes a successful adjustment of large tailor-made channels by the [2 + 2] cycloaddition reaction. The gas-chromatographic separation experiments show that ethanol can be better separated from water through a column filled with a post-cycloaddition modified sample than the as-synthesized one.

Two isomorphous halogen-bridged metal-organic frameworks have been solvothermally synthesized based on the bipyridinium ligand and structurally characterized. The two compounds show an eye-detectable color development upon light irradiation, but different coloration degrees. The relationship between the structure and photosensitivity has been studied in detail. The photochromic properties of the bipyridinium unit have been used to modulate the luminescence under light illumination. Compound 1 is the first example showing photo-modulated luminescence switching featuring a non-destructive readout capability based on transition metals.

The bpy, dpe and dppe were introduced as auxiliary ligands, respectively, to construct three magnesium-1,4-NDC coordination polymers (Mg-CPs) that exhibited tunable photoluminescence (PL) and direct white-light emission upon varying the excitation light.

A metal-organic framework (MOF) featuring intriguing Borromean entanglement exhibits a unique mechanochromic luminescence with on-off switching. The concomitant excitation wavelength-dependent emission behavior can be utilized to tune the emission color from violet to orange.

Twelve isostructural rare earth metal-organic frameworks, namely, [Hmim][RE(2)Cl(1,4-NDC)(3)] (RE = La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8), Dy (9), Ho (10), Er (11), Y (12), Hmim = 1-hexyl-3-methylimidazolium, 1,4-NDCH(2) = 1,4-naphthalenedicarboxylic acid), have been ionothermally synthesized and structurally characterized. The structures feature three-dimensionally anionic frameworks of [RE(2)Cl(1,4-NDC)(3)](n)(n-) with channels in which the Hmim(+) cations are located. The current results are the first ionothermal synthesis of rare earth metal-organic frameworks based on 1,4-NDCH(2) which possess a previously unknown (4,7)-connected 3-nodal network with the Schläfli symbol of (3(2)·4(2)·5(2))(3(2)·4(9)·5(2)·6(8))(2)(4(3)·6(3))(2). Luminescent and magnetic properties of some of the title compounds have been studied. Thermogravimetric analyses indicated that all these compounds were thermally stable up to ca. 250 °C.

A highly efficient organocatalytic sequential reaction involving Michael addition of bis(phenylsulfonyl)ethylene, in situ condensation and intramolecular nitrone [3+2] cycloaddition with a variety of aldehydes and hydroxyamines to afford a single diastereomer of indanes with four stereogenic centers in excellent yields and stereoselectivities was developed.

A novel HOTf-catalyzed three-component one-pot cycloaddition of alpha-diazo ester, nitrosobenzene and electron deficient alkene has been developed. This catalysis is very simple to operate and tolerant to moisture/oxygen to afford the product with high to excellent diastereoselectivity in good to excellent yield, thus providing a useful and convenient method for the preparation of diverse functionalized isoxazolidines under very mild conditions.

The first Michael addition of 1,3-diaryl-1,3-propanedione to nitroolefins was demonstrated using a simple organocatalyst, which afforded excellent yields (81-97%) and enantioselectivities (90 to >99% ee); the catalyst and excess reactant can be reused seven times through a simple filtration operation.