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The on-surface dimerization into bis(hexahelicene) on a gold(111) surface has been studied by means of scanning tunneling microscopy and time-of-flight secondary mass spectrometry. C-C Ullmann coupling of (rac)-2-bromo-hexahelicene leads to formation of the (M,M)- and (P,P)-diastereomers of 2,2'-bis(hexahelicene), whilst formation of the (M,P)-diastereomer is not observed. Upon cooling, the bis(hexahelicene) aggregates into an ordered two-dimensional lattice with partly randomly distributed enantiomers. The highly specific diastereomeric coupling is explained by the surface alignment of educt in combination with the strong steric overcrowding in a possible surface-confined (M,P)-product.
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http://dx.doi.org/10.1002/chem.202300134 | DOI Listing |
Mar Environ Res
September 2025
Shanghai Engineering Research Center of Hadal Science and Technology, College of Oceanography and Ecological Science, Shanghai Ocean University, Shanghai, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China. Electronic
Microbial extracellular alkaline phosphatase (ALP) plays a significant role in marine phosphorus cycle. Therefore, it is of paramount importance to accurately and rapidly measure ALP activity (APA) in seawater. However, the applications of the existing APA measurement methods are constrained by cumbersome pre-processing, lengthy measurement times, and the influence of colored substances or suspended particles in seawater samples, which limit our accurate understanding of the marine phosphorus cycle.
View Article and Find Full Text PDFAcc Chem Res
August 2025
Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstraße 2, 04103 Leipzig, Germany.
ConspectusIn this Account, we will focus on how chemoselective strategies were employed for the controlled synthesis of organic multilayers on silicon, thus forming well-defined semiconductor-organic interfaces. We will start with the chemoselective [2 + 2] cycloaddition of functionalized cyclooctynes to Si-Si dimers which was used as the key step for the surface-orthogonal first layer attachment of bifunctional organic molecules to the Si(001) surface. It results in well-ordered monolayers of bifunctional molecules on the highly reactive Si(001) surface, which serve as a starting point for the further layer-by-layer growth.
View Article and Find Full Text PDFJ Phys Chem Lett
July 2025
National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, People's Republic of China.
The incorporation of heterogeneous nodes can significantly enhance the catalytic and optoelectronic properties of metal-organic networks (MONs) because of the resulting uneven charge distribution and unique metal centers. On-surface synthesis (OSS) has emerged as a powerful strategy for constructing advanced MONs with heterogeneous metal-organic nodes. Herein, we report the fabrication of an MON featuring N-Ag-C heterogeneous nodes, achieved via thermally induced sequential N-OH and C-H activation on Ag(100).
View Article and Find Full Text PDFBiosens Bioelectron
November 2025
Hebei Key Laboratory of Photoelectric Control on Surface and Interface, College of Sciences, Hebei University of Science and Technology, Shijiazhuang, 050018, China. Electronic address:
Accurate and sensitive detection of amyloid-β oligomer (AβO) is essential for understanding the development and progression of Alzheimer's disease (AD). Herein, an ultrasensitive photoelectrochemical (PEC) biosensing platform was developed by integrating photoelectrically active porphyrin-based covalent organic frameworks with Fe single-atom catalysts (Fe SACs) to enhance PEC signal. The Fe SACs demonstrate remarkable peroxidase-like activity, enabling them to oxidize 4-chloro-1-naphthol (4-CN) to generate insoluble 4-chloro-1-naphthol dimer (4-CD) precipitation on the photoelectrode surface.
View Article and Find Full Text PDFNat Commun
June 2025
Physikalisches Institut, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany.
The design and control of atomic-scale spin structures constitute major challenges for spin-based quantum technology platforms, including quantum dots, color centers, and molecular spins. Here, we showcase a strategy for designing the quantum properties of molecular spin qubits by combining tip-assisted on-surface assembly with electron spin resonance scanning tunneling microscopy (ESR-STM): We fabricate magnetic dimer complexes that consist of an iron phthalocyanine (FePc) molecule and an organometallic half-sandwich complex formed by the FePc ligand and an attached iron atom, Fe(CH). The total complex forms a mixed-spin (1/2,1) quantum ferrimagnet with a well-separated correlated ground state doublet, which we utilize for coherent control.
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