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Amorphous carbon-supported sulfonic acid (AC–SO3H) is known as a new-generation solid catalyst with exceptional activity in organic synthesis. We report here the synthesis of sulfonated amorphous carbon, that possesses sulfonic acid groups, via the partial carbonization and then sulfonation of rice husk. The presence of –SO3H groups on the surface of the amorphous carbon significantly increased the catalytic activity in organic synthesis. In this study, the catalytic activity of AC–SO3H in the synthesis of 3-cyanoacetamide pyrrole from 1,3-diketones, primary amines, phenylglyoxal monohydrate, and malononitrile in acetone was assessed. We investigated the influence of the amine derivatives on the reaction outcome and the formation of by-products during the reaction. The main product was obtained in yields of up to 67%. The activity of the catalyst was also evaluated through a leaching test, whilst the recovery and reuse efficiency of the catalyst was also studied, with a negligible reduction in activity observed. [ABSTRACT FROM AUTHOR]

There has been growing interest in employing metal–organic frameworks (MOFs) incorporated with biomolecules, known as b-MOFs, in biomedical applications. However, it is difficult and challenging to synthesize these materials at the nanoparticle size because of their complex structures constructed from long organic linkers. Herein, we demonstrate the facile and successful synthesis of b-Zn-BPDC and b-Zn-azoBDC, nano-b-MOFs containing nucleobase adenine as biomolecular building blocks, by utilizing surfactants and a post-synthesis linker-exchange method, respectively. Due to its large pore size (26 Å), the linker-exchanged MOF nanomaterial exhibited a higher loading capacity of paclitaxel (PTX), a water-insoluble anticancer drug, than its original framework (948.11 vs. 713.43 mg g−1). Furthermore, the release profiles of PTX loaded b-MOF nanomaterials in phosphate buffered saline (PBS) displayed an increase in PTX solubility with a substantial initial drug release, followed by a progressive release over time. These results suggested that nano-b-MOFs can deliver hydrophobic anticancer drugs. [ABSTRACT FROM AUTHOR]

The catalytic properties of metal–organic frameworks (MOFs) containing triangular Fe(III) clusters in the promotion of organic syntheses and photocatalysis applications have been receiving substantial attention for decades. These clusters are appealing due to the strong Lewis acidity afforded by coordinatively unsaturated sites upon the removal of solvent from the framework. In this paper, triangular Fe(III) cluster-based MOFs were shown to be highly efficient heterogeneous catalysts for the solvent-free one-pot condensation of 2-aminobenzamide and alcohols to form quinazolin-4-ones under microwave irradiation. The Fe-MOF catalysts ranging from microporous to mesoporous structures with a variety of geometrical pore structures were investigated. Because of the open accessible spaces for reactants and high density of active sites, MOF-907, built from trimer Fe clusters and a mixture of two linkers, was more effective than other Fe(III)-MOFs. The catalyst can be used for a broad substrate scope and recycled several times without a significant drop-off in its activity. [ABSTRACT FROM AUTHOR]

In this work, ZnO nanoparticles (NPs) are synthesized using avocado seed extract and annealed at different annealing temperatures from 400 to 800 °C. The morphology of the nanoparticles changes from poly shapes at 400 °C to spherical ones at 800 °C, and particle sizes increase from ∼42 nm to ∼128 nm. The Ag/ZnO@400/FTO memory device exhibits stable resistive switching over 100 cycles and a resistance window of approximately 150. Also, the performance characteristics of ZnO@600 and ZnO@800-based devices are degraded gradually over operating cycles. The concentration of oxygen interstitials (O i ) in ZnO nanoparticles, which may originate from organic residues, decreases as the annealing temperature increases. These O i ions reduced the energy barrier at the interfaces, facilitating electron transport under an external electric field. This study has demonstrated the close correlation between resistive switching characteristics and organic residuals in green synthesized nanoparticles., Competing Interests: The authors have no conflicts to disclose. The XRD, FTIR, Raman, XPS and EDX data of the ZnO@400 sample were reprinted with permission from ref. 40., (This journal is © The Royal Society of Chemistry.)

Superacid VNU-11-SO 4 , a modified metal-organic framework by post-synthetic treatment with a sulfuric acid solution, has been considered as a promising heterogeneous catalyst in the isomerization of glucose to fructose and further dehydration to form 5-hydroxymethylfurfural (HMF) due to its possession of both Lewis and Brønsted acid sites. In this work, we focused on using VNU-11-SO 4 for the optimization of the conversion of fructose and glucose into HMF using an ionic liquid as a green solvent. The highest yields of HMF from glucose and fructose could be obtained in 28% (140 °C, 8 h) and 86% (110 °C, 3 h), respectively, with the use of VNU-11-SO 4 catalyst in 1-ethyl-3-methylimidazolium chloride ionic liquid. Recycling examination of the catalyst showed only a slight decrease in the HMF yield, implying its potential industrial application in biomass transformation., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)