A series of Ru(II) catalysts were prepared and tested in the asymmetric transfer hydrogenation of ketones. The catalyst containing a "4-carbon" tether gave the fastest rates of ketone reduction. This is due to both increased rate of regeneration of hydride "Ru-H" and increased rate of ketone reduction. Several classes of ketone were reduced in enantiomeric excesses of up to 97%. Substituents on the arene ring of the catalyst influence the reaction rate and enantioselectivity.
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The detection of mercury ions (Hg) is crucial due to its harmful effects on health and environment. In this article, what we believe to be a novel dual-mode optical fiber sensor incorporating surface plasmon resonance (SPR) and surface-enhanced Raman scattering (SERS) is proposed for ultra-trace Hg detection. The sensing probe comprises gold (Au)/graphene oxide (GO) composite membrane structure and Au nanospheres (AuNPs), which are connected via double-stranded DNA.
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December 2024
A partially disembodied quantum state transfer (PDQST) machine is crucial for Gaussian quantum information processing. It integrates Gaussian quantum teleportation and Gaussian quantum cloning machines into a single quantum information platform and therefore enhances the multifunctionality and compatibility of the present quantum information system. However, the standard PDQST machine relies on infinite quantum squeezing, which is unachievable in the practical implementation.
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January 2025
College of Chemistry and Pharmaceutical Engineering, Huanghuai University, Zhumadian 463000, PR China. Electronic address:
FeO nanoparticles (NPs) have emerged as pioneering nanozymes with applications in clinical diagnosis, environmental protection and biosensing. However, it is currently limited by insufficient catalytic activity due to poor electron transfer. In this study, we synthesized electron-rich-Zr-doped defect-rich FeO NPs (ZrFeO) using a one-pot solvothermal method.
View Article and Find Full Text PDFUnlabelled: Asymmetric cell division is used by stem cells to create diverse cell types while self-renewing the stem cell population. Biased segregation of molecularly distinct centrosomes could provide a mechanism to maintain stem cell fate, induce cell differentiation or both. However, the molecular mechanisms generating molecular and functional asymmetric centrosomes remain incompletely understood.
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January 2025
College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
Multicomponent reactions (MCRs), highly sought-after methods to produce atom-, step-, and energy-economic organic syntheses, have been developed extensively. However, catalytic asymmetric MCRs, especially those involving radical species, remain largely unexplored owing to the difficulty in stereoselectively regulating the extraordinarily high reactivity of open-shell radical species. Herein, we report a conceptually novel catalytic asymmetric three-component radical cascade reaction of readily accessible glycine esters, α-bromo carbonyl compounds and 2-vinylcyclopropyl ketones via synergistic photoredox/Brønsted acid catalysis, in which three sequential C-C (σ/π/σ) bond-forming events occurred through a radical addition/ring-opening/radical-radical coupling protocol, affording an array of valuable enantioenriched unnatural α-amino acid derivatives bearing two contiguous stereogenic centers and an alkene moiety in moderate to good yield with high diastereoselectivity, excellent enantioselectivity and good -dominated geometry under mild reaction conditions.
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