Direct C-H bond oxidation of organic materials, and producing the necessary oxygenated compounds under mild conditions, has attracted increasing interest. The selective oxidation of various alkylbenzenes was carried out by means of a new catalyst containing VO species supported on silica-coated FeO nanoparticles using -butyl hydroperoxide as an oxidant at room temperature in HO or solvent-free media. The chemical and structural characterization of the catalyst using several methods such as FTIR spectroscopy, XRD, FETEM, FESEM, SAED, EDX and XPS showed that VO is covalently bonded to the silica surface. High selectivity and excellent conversion of various toluene derivatives, with less reactive aliphatic (sp) C-H bonds, to related benzoic acids were quite noticeable. The aerobic oxygenation reaction of these alkylbenzenes was studied under the same conditions. All the results accompanied by sustainability of the inexpensive and simple magnetically separable heterogeneous catalyst proved the important criteria for commercial applications.
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http://dx.doi.org/10.1039/d0ra03483e | DOI Listing |
J Chromatogr A
January 2025
Nicolaus Copernicus University in Toruń, Interdisciplinary Centre of Modern Technologies, Wileńska 4, 87-100, Toruń, Poland; Nicolaus Copernicus University in Toruń, Faculty of Chemistry, Department of Environmental Chemistry and Bioanalytics, Gagarina 7, PL-87-100 Toruń, Poland; Prof. Jan Czochralski Kuyavian-Pomeranian Research & Development Centre, Krasińskiego Str. 4, 87-100 Toruń, Poland. Electronic address:
This work presents, for the first time, the preparation method and subsequent use of biosilica in column liquid chromatography in reverse-phase mode. Diatom biosilica consists of the siliceous exoskeletons (frustules) of unicellular algae. Controlled cultivation of Pseudostaurosira trainorii diatoms resulted in frustules with an average diameter of approximately 4 µm, sidewall thickness of 1 µm, and a bottom thickness of 110-150 nm.
View Article and Find Full Text PDFChem Commun (Camb)
October 2024
State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, People's Republic of China.
A straightforward method for the dehydrogenative alkylation of quinoxalin-2(1)-ones with alkylbenzenes has been developed, facilitated by a photoexcited nitroarene. The reaction's success hinges on the dual role of the photoexcited nitroarene molecule, acting as both a hydrogen atom transfer (HAT) reagent and an oxidant. This technique is both atom-economical and cost-effective, due to the readily available nitroarene, which serves as the sole intermediary in the reaction process.
View Article and Find Full Text PDFJ Chromatogr A
August 2024
School of Pharmacy, Jining Medical University, Jining 272000, PR China. Electronic address:
The epoxy propanol molecular cage bonded silica stationary phase, RCC3-GLD@silica, synthesized through the ring-opening reaction of secondary amine with epoxy propanol using RCC3-R as the scaffold unit, was successfully prepared as confirmed by infrared spectroscopy, thermogravimetric analysis, and nitrogen adsorption-desorption characterization. This stationary phase demonstrated excellent separation performance in both reversed-phase and hydrophilic chromatography modes, effectively separating a wide variety of compounds including alkylbenzenes, polycyclic aromatic hydrocarbons, phenols, anilines, sulfonamides, nucleosides, amino acids, sugars, and acids. The development of RCC3-GLD@silica benefits from the synergistic effects of its hydrophobic and hydrophilic actions, as evidenced by the U-shaped characteristic of the retention factor for nucleoside compounds with changes in the aqueous content of the mobile phase, further confirming the simultaneous presence of reversed-phase and hydrophilic chromatography mechanisms.
View Article and Find Full Text PDFFaraday Discuss
September 2024
CAS Key Laboratory of Biofuels and Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China.
Cytochrome P450 monooxygenases (P450s) are well recognized as versatile bio-oxidation catalysts. However, the catalytic functions of P450s are highly dependent on NAD(P)H and redox partner proteins. Our group has recently reported the use of a dual-functional small molecule (DFSM) for generating peroxygenase activity of P450BM3, a long-chain fatty acid hydroxylase from .
View Article and Find Full Text PDFJ Chromatogr A
August 2024
Key Laboratory of Synthetic and Natural Functional Molecule of Ministry of Education, Institue of Modern Separation Science, Key Lab of Modern Separation Science in Shaanxi Province, College of Chemstry & Materials Science, Northwest University, Xi'an 710127, China. Electronic address:
Covalent organic frameworks (COFs) show promise as a stationary phase in high performance liquid chromatography (HPLC). However, there are only a few COFs-based stationary phases developed for HPLC separation so far. Therefore, it is crucial to not only develop more varieties of COFs-type stationary phases for HPLC separation, but also to explore the retention mechanism of solutes on these stationary phases.
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