A Ni-catalyzed reductive coupling of alkynes and epoxides using Ni(II) salts and simple alcohol reducing agents is described. Whereas previously reported conditions relied on Ni(cod)(2) and Et(3)B, this system has several advantages including the use of air-stable and inexpensive Ni(II) precatalysts (e.g., NiBr(2)·3H(2)O) as the source of Ni(0) and simple alcohols (e.g., 2-propanol) as the reducing agent. Deuterium-labeling experiments are consistent with oxidative addition of an epoxide C-O bond that occurs with inversion of configuration.
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http://dx.doi.org/10.1021/ol201702a | DOI Listing |
Biometals
December 2024
Department of Chemistry, Baba Mastnath University, Asthal Bohar, Rohtak, 124021, India.
The Schiff base metal complexes containing the transition metal ions Co(II), Ni(II) and Cu(II) were synthesized using their nitrate and acetate salts. An octahedral environment encircling metal complexes has been demonstrated by the findings of multiple spectroscopic approaches that were employed to demonstrate the structure of the metal complexes. The Coats-Redfern method of thermal analysis was employed to carry out the kinetic and thermodynamic calculations.
View Article and Find Full Text PDFInorg Chem
December 2024
Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States.
Mono-β-diketonate compounds have been fleetingly observed in base metal catalyzed reactions, which are of current interest as alternatives to precious metal catalyzed reactions. Their isolation has been challenging due to synthetic and structural limitations of acac-type ligands, leading to the development of a related NacNac ligand platform. Herein we report the synthesis of a β-diketone capable of kinetically stabilizing relevant catalytic intermediates.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
School of Chemical Engineering, Changchun University of Technology, Changchun 130012, China. Electronic address:
Anthropogenic wastewater generation and water pollution can have negative impacts on public health and ecosystems. However, most materials do not have both adsorptive and catalytic properties, so the design and development of sustainable and multifunctional materials is essential for wastewater treatment. Herein, composite hydrogel (PHG) containing [2-(Methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide (SBMA) and chitosan quaternary ammonium salts (HACC) were prepared for wastewater treatment.
View Article and Find Full Text PDFChem Biodivers
September 2024
Department of Chemistry, Faculty of Science, Sohag University, Sohag, 82524, Egypt.
Mixed-ligand complexes incorporating 1H-Imidazole-2-Carboxylic acid (IMCA) and Histidine (LHIS) show promise for biomedical and biotechnological applications. This study synthesizes and characterizes FeIMCALHIS, CoIMCALHIS, and NiIMCALHIS coordination compounds using metal chloride salts (FeCl.6HO, CoCl.
View Article and Find Full Text PDFDalton Trans
September 2024
Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, 721302 India.
A series of new bis(phenylthioether) and bis(benzylthioether) compounds (L1-L5) having hexahydropyrimidine, imidazolidine and dihydroperimidine backbones were synthesized. Instead of giving NHC complexes, these compounds undergo facile C-S bond cleavages upon treatment with Ni(II) salts to selectively give new toroidal Ni(II) thiolates: [Ni(SPh)] (1) and [Ni(SCHPh)] (5), and the known [Ni(SCHPh)] (8), as confirmed by single crystal X-ray diffraction studies. By-products such as RSSR (R = Ph and CHPh) and partially C-S bond cleaved starting compounds were isolated or detected as well from these reactions.
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