The reaction of (S)-alpha-(1-hydroxyalkyl)vinyl sulfoxides (S)-5 with alkyl radicals and tributyltin hydride gave the addition-hydrogenation products with high diastereoselectivity, whereas the reaction with (R)-alpha-(1-hydroxyalkyl)vinyl sulfoxides (R)-5 resulted in complete recovery of the starting sulfoxides. Stereoselective intramolecular hydrogen bonding between the hydroxy group and the diastereotopic sulfonyl oxygen led to high diastereoselectivity in the radical reaction of alpha-(1-hydroxyethyl)vinyl sulfone 12. An important role of intramolecular hydrogen bonding on the diastereoselectivity as well as the reactivity toward alkyl radicals is discussed.
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http://dx.doi.org/10.1021/jo005525o | DOI Listing |
Spectrochim Acta A Mol Biomol Spectrosc
January 2025
Key Laboratory for Microstructural Material Physics of Hebei Province, School of Science, Yanshan University, Qinhuangdao 066004 PR China. Electronic address:
2-{[3-(1H-benzoimidazol-2-yl)-2-hydroxy-5-methylbenzylidene] amino}-benzoic acid (HBIo) based on proton transfer can serve as the fluorescent probe for detecting heavy metal ions. The excited-state intramolecular proton transfer (ESIPT) reaction mechanism of the HBIo chromophore with an intramolecular asymmetric double hydrogen bond in different solvents are investigated. The reaction barrier of the ESIPT along hydrogen bond O1-H2···N3 is higher than that of ESIPT along O4-H5···N6, which indicates that the double ESIPT is a stepwise process.
View Article and Find Full Text PDFJ Mol Graph Model
January 2025
Unit of Excellence in Computational Molecular Science and Catalysis, and Division of Chemistry, School of Science, University of Phayao, Phayao, 56000, Thailand. Electronic address:
Monomer insertion, leading to the formation of an activated monomer complex, is a critical step in cationic ring-opening polymerization (CROP) of cyclic monomers, such as ε-caprolactone (CL). In this study, Density Functional Theory (DFT) calculations were employed to investigate the structural and electronic properties of four activated complexes at two Zr:B ratios (1:2 and 1:1), where Zr is the cationic zirconocene catalyst, Cp₂ZrMe⁺, and B is the borate cocatalyst, [MeB(CF)] or [B(CF)]. Steric hindrance at the reactive site was analyzed using topographic steric maps, while inter- and intramolecular interactions of the complex systems were examined through the Quantum Theory of Atoms in Molecules (QTAIM) and non-covalent interaction (NCI) analyses.
View Article and Find Full Text PDFDalton Trans
January 2025
Organometallics and Materials Chemistry Lab, Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Telangana, 502285, India.
The assessment of copper(I) and hydrogen interactions is challenging and should be approached with caution. In this paper, we report an assessment of multiple copper(I) and hydrogen interactions in two unique copper(I) thione cages. Copper(I) -heterocyclic thione cages [{Cu(-Br)(-L1)}] (1) and [{Cu(-I)(-L1)}] (2) were synthesized and characterized with proximity enforced Cu⋯H interactions.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
University of Regensburg, Faculty of Chemistry and Pharmacy, Institute of Inorganic Chemistry, Universitätsstraße 31, D-93053, Regensburg, GERMANY.
Aminophosphates are the focus of research on prebiotic phosphorylation chemistry. Their bifunctional nature also makes them a powerful class of organocatalysts. However, the structural chemistry and dynamics of proton-binding in phosphorylation and organocatalytic mechanisms are still not fully understood.
View Article and Find Full Text PDFChemistry
January 2025
university of science and technology of china, School of Nuclear Science and Technology, China, 230029, HEFEI, CHINA.
The final outcomes of supramolecular assembly are determined by the pathways and the formation of intermediates during the assembly process. We studied pathway complexity involving two consecutive pathways in supramolecular polymerization of naphthalene-diimide (NDI) derivative molecule. Depending on preparation methods anisotropic aggregates of J-type nanorods (Agg I) or more flexible H-type nanofibers (Agg II) are obtained from the identical initial state in solution of methyl cyclohexane (MCH) or MCH/CHCl3 mixtures.
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