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The push for environmentally benign and sustainable chemical processes has reinforced the demand to displace transition metals with cheap, nontoxic and naturally abundant metals. To fulfil this requirement, we endeavored to synthesize alkali- and alkaline earth-metal complexes and employ them as catalysts for organic transformations. Two lithium and one magnesium complexes, which are supported by pyridyl-pendanted unsymmetrical β-diketiminates, have been synthesized and characterized. They are formulated as [Li(L

A unified catalytic asymmetric (N+1) (N=4, 5) annulation reaction of oxindoles with bifunctional peroxides has been achieved in the presence of a chiral phase-transfer catalyst (PTC). This general strategy utilizes peroxides as unique bielectrophilic four- or five-atom synthons to participate in the C-C and the subsequent umpolung C-O bond-forming reactions with one-carbon unit nucleophiles, thus providing a distinct method to access the valuable chiral spirooxindole-tetrahydrofurans and -tetrahydropyrans with good yields and high enantioselectivities under mild conditions. DFT calculations were performed to rationalize the origin of high enantioselectivity. The gram-scale syntheses and synthetic utility of the resultant products were also demonstrated.

Employing FeCl

An efficient cobalt-catalyzed geometrical isomerization of 1,3-dienes is described. In the combination of a CoCl

Metal–organic frameworks (MOFs) as adsorbents have attracted interest in water-based adsorption applications due to their typical S-shape vapor adsorption isotherms and low regeneration temperature...

MIL-100(Fe) has been proven to have good hydrothermal stability and high vapor uptake and is considered as a promising dehumidification material. However, reduction of the production cost and assem...

Owing to the features of S-shape water sorption isotherm and low desorption temperature, MIL-101(Cr) has been considered as up-and-coming adsorbent for adsorption heat pumps (AHPs). In order to improve water vapor uptake at the low relative pressure (P/P0 ≤ 0.3) for AHPs, a new type of solid adsorbent was fabricated by impregnating porous MIL-101(Cr) with the aqueous solution of hygroscopic salt such as CaCl2 and LiCl. The effect of impregnation salt concentration on hygroscopicity of composite salt-MIL-101(Cr) was discussed. The crystalline phase, pore structure, morphology and the composition of the composites were characterized by X-ray diffraction, pore size analysis, Scanning Electron Microscopy and Energy Dispersive Spectrometry. And their adsorption and desorption performances were evaluated. The experimental results indicated that the composites obtained by dipping MIL-101(Cr) with the solution of 25% CaCl2 and 15% LiCl, exhibited excellent adsorption capacities and fast adsorption rates. Their amounts adsorbed at P/P0 of 0.3 reached 0.44, 0.45 g/g, respectively, which were much higher than the pristine MIL-101(Cr). Additionally, fifty separate adsorption/desorption cycles suggested that the composite had excellent reversibility. All the results indicated that the novel composite salt-MIL-101(Cr) are expected to be a promising candidate for AHPs.

The monolithic adsorbent is a key part of an adsorptive rotary dehumidification system. It is usually prepared by dip-coating the adsorbent on glass fiber paper. In this study, a new in situ strategy for synthesis of an aluminum fumarate (A520) metal–organic framework monolithic adsorbent on glass fiber paper is introduced. The influences of the mole ratio of fumaric acid to H2O, the reaction temperature and time on the crystal phase, the pore structure, and the adsorption performance of the monolithic adsorbent are systematically discussed. The morphology of the adsorbent was characterized by scanning electronic microscopy, and the adsorption and desorption performances were evaluated by dynamic vapor sorption and differential thermogravimetric analysis. The results showed that under the conditions of a mole ratio of fumaric acid to H2O of 0.02, reaction temperature of 50 °C, and reaction time of 60 min, the obtained A520 monolith exhibited the highest BET surface area (740.15 m2·g–1) and high adsorption...

With an S-shaped water sorption isotherm and high vapor uptake, as one of the famous metal organic frameworks (MOFs), MIL-100(Fe) (MIL stands for Materials of Institute Lavoisier) has been consider...

As one of typical metal organic frameworks (MOFs), MIL-101 (Cr) has potential application in adsorption heat pumps. However, traditional hydrothermal synthetic technology of MIL-101 (Cr) requires h...

The

Development of multifunctional probes that can be simultaneously utilized for both efficient hydrogen sulfide detection and photodynamic therapy in cancer cells is in high demand but remains worldwide challenge. Herein, a fluorescent probe DB2T based on a BODIPY structure for H2S fluorescence “turn-on” detection together with light sensitive anticancer capacity has been designed and synthesized. The probe DB2T features high selectivity towards H2S, excellent low detection limit (6.39 nM), and good biocompatibility. Importantly, the probe DB2T has been satisfactorily applied in fluorescence imaging of exogenous H2S in zebrafish, and successfully employed in fluorescence imaging of endogenous H2S in HCT116 cell and tumor tissues. Moreover, evaluation of the phototherapy effect demonstrates that the probe DB2T performs well as a photosensitizer for photodynamic ablation of HCT116 cancer cells upon white light irradiation. This work should facilitate significant advances in rational design of fluorescence systems for H2S detection and even in the diagnosis and treatment of H2S related diseases.

With a characteristic of S-shape isotherms for water vapor adsorption, aluminophosphate molecular sieve with AFI type (AlPO-5) has been considered as an up-and-coming adsorbent for the utilization in the adsorption cooling and heating (ACH) system. In order to improve its adsorption performance, iron doped AlPO-5 (FeAPO-5) with variable Fe loading was synthesized by microwave hydrothermal method. The effects of the iron doping content on the structure and adsorption performance were systematically investigated. The analysis results of X-ray diffraction (XRD), UV–visible spectroscopy (UV–Vis-DR) and scanning electron microscopy (SEM) showed that the iron ion was incorporated into aluminophosphate molecular sieves with a typical AFI structure as that of AlPO-5 through the isomorphous substitution. As the iron content of FeAlPO-5s increased, the isolated FeIII decreased, while oligonuclear FeIII and nanosized FeIII increased, besides, the static adsorption curves showed that the adsorption capacity of FeAlPO-5 increased first and then decrease. After iron modifying, the crystallinity and morphology of crystals was improved, and the adsorption performance increased from 0.185 g/g (AlPO-5A) to 0.235 g/g (FeAlPO-5), while the desorption performance of FeAlPO-5 (95.69 kJ/mol) was close to that of AlPO-5A (81.59 kJ/mol).

Metal organic frameworks (MOFs) MIL-100(Fe) is considered to be a promising porous adsorbent for dehumidification due to its good hydrophilicity and hydrothermal stability. However, the powdery MIL-100(Fe) prepared by the conventional hydrothermal method is not suitable for industrial rotary desiccant dehumidifier. In order to produce a high-performance rotor core component, a new dry gel conversion in situ synthesis strategy for glass-fiber MIL-100(Fe) monolithic adsorbent was proposed in this paper. The effects of the reaction sol concentration on the crystalline phase, morphology, pore structure, adsorption/desorption performance and the cycling stability of the monolith were discussed in detail. The results showed that MIL-100(Fe) crystals which evenly dispersed in the surface and voids of glass fiber, could be conveniently synthesized in the reaction sols with molar ratios of 1Fe (III)/0.67BTC/xH2O (x = 93–185). Among them, the MIL-100(Fe) monolith obtained at x = 93 exhibited a high loading (85.7%), large BET specific surface area (1441 m2/g), S-shaped water vapor adsorption isotherm and high saturated adsorption ratio (0.496 g/g) at 298 K and 60% RH, low desorption activation energy (48.28 kJ/mol) as well as a reliable cycling stability. Favorable adsorption/desorption performance of MIL-100(Fe) monolith and convenient dry gel preparation process provide a guidance for the manufacture of high-performance dehumidification rotary wheel.