Nano-eggshell/Ti(IV) as a novel naturally based catalyst was prepared, characterized and applied for the synthesis of dihydropyrano[2,3-c]pyrazole derivatives. The characterization of nano-eggshell/Ti(IV) was performed using Fourier Transform Infrared spectroscopy, X-ray Diffraction, Field Emission Scanning Electron Microscopy, Energy-Dispersive X-ray Spectroscopy, and Thermo Gravimetric Analysis. Dihydropyrano[2,3-c]pyrazoles were synthesized in the presence of nano-eggshell/Ti(IV) via a four component reaction of aldehydes, ethyl acetoacetate, malononitrile and hydrazine hydrate at room temperature under solvent free conditions. The principal affairs of this procedure are mild condition, short reaction times, easy work-up, high yields, reusability of the catalyst and the absence of toxic organic solvents.
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http://dx.doi.org/10.1186/s13065-021-00734-5 | DOI Listing |
Nat Chem Biol
January 2025
State Key Laboratory of Chemo/Biosensing and Chemometrics and School of Chemistry and Chemical Engineering, Hunan University, Changsha, China.
Artificial metalloenzymes (ArMs) integrated within whole cells have emerged as promising catalysts; however, their sensitivity to metal centers remains a systematic challenge, resulting in diminished activity and turnover. Here we address this issue by inducing in cellulo liquid-liquid phase separation through a self-labeling fusion protein, HaloTag-SNAPTag. This strategy creates membraneless, isolated liquid condensates within Escherichia coli as protective compartments for the assembly of ArMs using the same fusion protein.
View Article and Find Full Text PDFNature
January 2025
Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA.
The low reduction potentials required for the reduction of dinitrogen (N) render metal-based nitrogen-fixation catalysts vulnerable to irreversible damage by dioxygen (O). Such O sensitivity represents a major conundrum for the enzyme nitrogenase, as a large fraction of nitrogen-fixing organisms are either obligate aerobes or closely associated with O-respiring organisms to support the high energy demand of catalytic N reduction. To counter O damage to nitrogenase, diazotrophs use O scavengers, exploit compartmentalization or maintain high respiration rates to minimize intracellular O concentrations.
View Article and Find Full Text PDFInt Microbiol
January 2025
Center for the Development of Functional Materials (CDMF), Universidade Federal de São Carlos (UFSCar), Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905, Brazil.
Among the vast array of functional nanoparticles (NPs) under development, nickel tungstate (NiWO) has gained prominence due to its potential applications as a catalyst, sensor, and in the development of supercapacitors. Consequently, new studies on the environmental impact of this material must be conducted to establish a regulatory framework for its management. This work aims to assess the effects of NiWO (NPs) on multiple endpoints (e.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
National University of Singapore, Chemistry, 3 Science Drive 3, Singapore 117543, 117543, Singapore, SINGAPORE.
Copper-based catalysts are the choice for producing multi-carbon products (C2+) during CO2 electroreduction (CO2RR), where the Cu0Cuδ+ pair sites are proposed to be synergistic hotspots for C-C coupling. Maintaining their dynamic stability requires precise control over electron affinity and anion vacancy formation energy, posing significant challenges. Here, we present an in-situ reconstruction strategy to create dynamically stable Cu0Cu0.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Energy and Process Engineering Division, School of Mechanical, Medical and Process Engineering, Science and Engineering Faculty, Queensland University of Technology, 2 George Street, Brisbane City, Queensland 4001, Australia.
The strategic design and fabrication of efficient electrocatalysts are pivotal for advancing the field of electrochemical water splitting (EWS). To enhance EWS performance, integrating non-noble transition metal catalysts through a cooperative double metal incorporation strategy is important and offers a compelling alternative to conventional precious metal-based materials. This study introduces a novel, straightforward, single-step process for fabricating a bimetallic MoCo catalyst integrated within a three-dimensional (3D) nanoporous network of N, P-doped carbon nitride derived from a self-contained precursor.
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