Carbon-supported Pt nanoparticles (Pt/C) were found to be effective heterogeneous catalysts for the direct Julia olefination of alcohols in the presence of sulfones and KOtBu under oxidant-free conditions. Primary alcohols, including aryl, aliphatic, allyl, and heterocyclic alcohols, underwent olefination with dimethyl sulfone and aryl alkyl sulfones to give terminal and internal olefins, respectively. Secondary alcohols underwent methylenation with dimethyl sulfone. Under 2.5 bar H2, the same reaction system was effective for the transformation of alcohol OH groups to alkyl groups. Structural and mechanistic studies of the terminal olefination system suggested that Pt(0) sites on the Pt metal particles are responsible for the rate-limiting dehydrogenation of alcohols and that KOtBu may deprotonate the sulfone reagent. The Pt/C catalyst was reusable after the olefination, and this method showed a higher turnover number (TON) and a wider substrate scope than previously reported methods, which demonstrates the high catalytic efficiency of the present method.
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http://dx.doi.org/10.1002/chem.201505109 | DOI Listing |
Adv Mater
March 2025
PCFM Lab, School of Chemistry, Sun Yat-sen University, Guangzhou, 510006, P. R. China.
Exudate management and cell activity enhancement are vital to complicated wound healing. However, current exudate management dressings indiscriminately remove exudate, which is detrimental to cell activity enhancement. Herein, a novel class of electroactive bilayer (cMO/PVA) dressing is developed by constructing manganese oxide nanoneedle-clusters decorated commercial carbon cloth (MO), in situ casting polyvinyl alcohol (PVA) hydrogel, and finally charging.
View Article and Find Full Text PDFJ Biomed Mater Res B Appl Biomater
March 2025
Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA.
Designing biomimetic substrates and electrodes for bioelectronic devices with the necessary mechanical, electrical, and biological properties is critical considering the potential mismatch between soft tissue and rigid electronics, where incompatibility leads to decreased device performance, delamination, inflammation, and discomfort. There is an unmet engineering and clinical need for epidermal bioelectronics that are bioinert, can emulate host tissue mechanical properties, demonstrate low bulk resistivity, and are flexible and scalable. To address this shortcoming, this work describes innovations pertaining to the development of a hydrophilic, biocompatible nanocomposite comprised of carbon black (CB), polyvinyl alcohol (PVA), and glycerol for neuro-muscular and rehabilitative applications.
View Article and Find Full Text PDFFood Res Int
April 2025
State Key Laboratory of Bioactive Molecules and Druggability Assessment, Guangdong Basic Research Center of Excellence for Natural Bioactive Molecules and Discovery of Innovative Drugs, Institute for Advanced and Applied Chemical Synthesis, College of Pharmacy, Jinan University, Guangzhou 510632, China; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM & New Drugs Research, College of Pharmacy, Jinan University, Guangzhou 510632, China; Anhui Jinhe Industrial Co., Ltd., Chuzhou 239200, China. Electronic address:
Edible oleogels have recently attracted attention as new fat substitutes and as delivery systems. While thus having great potential, the oleogelators described thus far lack the necessary properties for extended deployment in a broad range of settings. Xylitol fatty acid monoesters have recently been identified as a novel class of oleogelator but little is currently known about how progression through an homologous series of congeners incorporating extended alkyl side-chains impacts on their properties.
View Article and Find Full Text PDFChem Sci
March 2025
D-CHAB, ETH Zürich Vladimir-Prelog-Weg 2 8093 Zürich Switzerland
Bimetallic heterogeneous catalysts combining group 9 metals (Rh, Ir) or group 10 metals (Ni, Pd, Pt) with Mo on a silica-based support have been synthesized surface organometallic chemistry and assessed in their catalytic activity for the hydrodeoxygenation (HDO) of alcohols with particular emphasis on the structural evolution of the catalysts and the role of Mo. The investigation was conducted with an air-free approach to isolate any sample alterations exclusively to those caused by the reaction. Structural analysis was performed using a combination of (S)TEM, IR, and XAS.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
July 2024
In this study, we present the development of a muscle phantom using a hydrogel composed of polyvinyl alcohol (PVA), agar, graphite, and NaCl, cross-linked through freeze/thaw cycling. We compared the properties of the PVA hydrogel with those of a PVA-agar hydrogel filled with graphite and NaCl. To characterize and optimize the mixtures, samples with varying graphite concentrations were prepared, and their electrical properties were measured using bioelectrical impedance spectroscopy (BIS) over a low-frequency range (1 kHz-1 MHz).
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