A mechanistic investigation of Ullmann-Goldberg reactions using soluble and partially soluble bases led to the identification of various pathways for catalyst deactivation through (i) product inhibition with amine products, (ii) by-product inhibition with inorganic halide salts, and (iii) ligand exchange by soluble carboxylate bases. The reactions using partially soluble inorganic bases showed variable induction periods, which are responsible for the reproducibility issues in these reactions. Surprisingly, more finely milled CsCO resulted in a longer induction period due to the higher concentration of the deprotonated amine/amide, leading to suppressed catalytic activity. These results have significant implications on future ligand development for the Ullmann-Goldberg reaction and on the solid form of the inorganic base as an important variable with mechanistic ramifications in many catalytic reactions.
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http://dx.doi.org/10.1039/c7sc02859h | DOI Listing |
Foods
January 2025
Department of Food Engineering, University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, 3-5 Calea Mănăştur, 400372 Cluj-Napoca, Romania.
The solid waste generated from processing rosehip fruits into jam is valuable due to its rich content in fibres, polyphenols, and carotenoids; it could be valorised as a functional ingredient in a powder form to enrich food products. This study aimed to test its potential as a value-added ingredient, especially to enrich waffle cones with fibres, polyphenols, and carotenoids. In this regard, four formulations of waffle cones were prepared by partially substituting wheat flour with rosehip waste powder at 0%, 10%, 15%, and 20%, reaching concentrations of 0%, 3.
View Article and Find Full Text PDFJ Cell Mol Med
January 2025
The Second Affiliated Hospital of Harbin Medical University, Heilongjiang, China.
Pulmonary fibrosis is a pathological manifestation that occurs upon lung injury and subsequence aberrant repair with poor prognosis. However, current treatment is limited and does not distinguish different disease stages. Here, we aimed to study the differential functions of Axl, a receptor tyrosine kinase expressing on both macrophages and fibroblasts, in the whole course of pulmonary fibrosis.
View Article and Find Full Text PDFFood Res Int
January 2025
College of Food and Biological Engineering, Chengdu University, Chengdu 610106, PR China. Electronic address:
Whole utilization of okara has important economic value, but there are two technical barriers: coarse mouthfeel caused by insoluble dietary fiber (IDF) and undesirable "beany" off-odors. UV-A irradiation and/or microbial fermentation were used to modify okara. The results indicated that single and combined treatments increased the soluble dietary fiber (SDF) content.
View Article and Find Full Text PDFInt Immunopharmacol
January 2025
Institute of Translational Medicine, School of Basic Medical, Hengyang Medical College, University of South China, Hengyang, Hunan 42100l, China. Electronic address:
Rheumatoid arthritis (RA) is a common chronic autoimmune disease that primarily affects the joints, leading to synovial inflammation and hyperplasia, which subsequently causes joint pain, swelling, and damage. The microenvironment of RA is characterized by hypoxia, high reactive oxygen species (ROS), low pH, and levels of high inflammatory factors. Traditional treatments only partially alleviate symptoms and often cause various adverse reactions with long-term use.
View Article and Find Full Text PDFPlants (Basel)
December 2024
Institut für Angewandte Wissenschaft, Ausbau 5, 18258 Rukieten, Germany.
Phosphate (P) is the plant macronutrient with, by far, the lowest solubility in soil. In soils with low P availability, the soil solution concentrations are low, often below 2 [µmol P/L]. Under these conditions, the diffusive P flux, the dominant P transport mechanism to plant roots, is severely restricted.
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