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Rapid and efficient access to structurally diverse β-fluoroalkylamines is in high demand, with their wide presence and great importance in medicinal chemistry and drug development. Direct 1,2-aminofluorination of alkenes offers an ideal strategy for one-step entry to β-fluorinated amines from readily available starting materials. Yet the synthesis of valuable β-fluorinated alkylamines remains an unsolved challenge, due to the inherent incompatibility between electrophilic fluoride sources and the electron-rich alkylamines. We report an unprecedented, catalytic, three-component aminofluorination of diverse alkenes and 1,3-dienes, which has been achieved by an innovative copper-catalyzed electrophilic amination strategy using O -benzoylhydroxylamines as alkylamine precursors. The use of Et 3 N·3HF is also critical, not only as a commercially available and inexpensive fluoride source to enable effective fluorination but also as an acid source for the formation of aminyl radical cations for electrophilic amination. Mechanistic experiments suggest the involvement of aminyl radical species and carbon-radical intermediates under reaction conditions. This method features high regioselectivity and good tolerance of diverse functional groups and provides a practical and direct entry to a broad range of β-fluorinated electron-rich alkylamines. Synthetic applications of this method have also been highlighted by its use for the rapid entry to β-fluoridated amine-containing pharmaceuticals, natural products, and bioactive compounds.

A novel silyl radical-induced cascade silylation/cyclization of 1,7-dienes has been realized employing readily available hydrosilanes as a silicon source and Cu(I) salt as a catalyst. This protocol introduces diverse silicon fragments into a challenging 7-membered ring structure and provides an efficient approach to a wide array of biologically important silyl-substituted benzo[b]azepin-2-ones. Several control experiments suggest that the reaction undergoes a free radical process. The gram-scale synthesis and late-stage transformations further demonstrate the scalability and applicability of the reaction in organic synthesis. [ABSTRACT FROM AUTHOR]

The activation of water molecules in thermal catalysis typically requires high temperatures, representing an obstacle to catalyst development for the low‐temperature water‐gas shift reaction (WGSR). Plasmonic photocatalysis allows activation of water at low temperatures through the generation of light‐induced hot electrons. Herein, we report a layered double hydroxide‐derived copper catalyst (LD‐Cu) with outstanding performance for the low‐temperature photo‐driven WGSR. LD‐Cu offered a lower activation energy for WGSR to H2 under UV/Vis irradiation (1.4 W cm−2) compared to under dark conditions. Detailed experimental studies revealed that highly dispersed Cu nanoparticles created an abundance of hot electrons during light absorption, which promoted *H2O dissociation and *H combination via a carboxyl pathway, leading to the efficient production of H2. Results demonstrate the benefits of exploiting plasmonic phenomena in the development of photo‐driven low‐temperature WGSR catalysts. [ABSTRACT FROM AUTHOR]

Methanol steam reforming (MSR) is viewed as an important technology in the growth of a future hydrogen economy, with methanol serving as an easily transportable and storable liquid hydrogen carrier. However, the thermocatalytic MSR reaction is energy intensive as it requires high temperatures. Herein, a novel L‐Cu catalyst is successfully fabricated for photo‐driven MSR through reduction of CuAl layered double hydroxide (CuAl‐LDH) nanosheets. L‐Cu offers outstanding activity for the photothermal conversion of methanol and water to hydrogen (160.5 µmol gcat−1 s−1) under ultraviolet‐visible irradiation, with this rate being much higher than that achieved for L‐Cu at the same temperature in the dark. Characterization studies using X‐ray diffraction, X‐ray photoelectron spectroscopy, X‐ray absorption spectroscopy, and high‐resolution transmission electron microscopy determine that L‐Cu catalyst comprise Cu nanoparticles on an amorphous alumina support. Computational calculations reveale that Cu localized surface plasmon resonance effects promote the activation of H2O, thereby underpinning the remarkable hydrogen production rates achieved during photo‐driven MSR. This study introduces a novel photothermal strategy for hydrogen generation from methanol, demonstrating the enormous potential of photothermal catalysis in the chemical and energy sectors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tin mineralization is related to the Early Cretaceous highly evolved granites. • The causative intrusions are formed in a low-P and high-T environment. • The injection of oxidized mafic magma plays a critical role to the Sn-Cu deposits. Granite-related hydrothermal Sn deposits are commonly expected to contain little or no Cu because Cu and Sn have markedly different geochemical properties. However, examples of Sn deposits rich in Cu are well-known in many Sn belts worldwide. So far, the magmatic processes of ore-related rocks and genesis of Cu-rich Sn deposits remain controversial. The newly discovered Yuanlinzi Sn-Cu deposit is located in the southern Great Xing'an Range (SGXR), Northeast China. It is a typical Cu-rich Sn deposit in the SGXR. This contribution reports new cassiterite and zircon U-Pb ages, geochemical compositions, and Sr-Nd isotopic data for the granitoids in the Yuanlinzi deposit to decipher the genesis of Cu-rich Sn deposit. Cassiterite U-Pb dating reveals that the Sn mineralization at Yuanlinzi was formed at ∼ 138 Ma. Zircon U-Pb dating of the granitoids yielded two age clusters: Early Triassic (247.6–246.3 Ma) for the granodiorite, and Early Cretaceous (145.3–141.9 Ma) for the granites, including K-feldspar granite (145.3 ± 0.5 Ma), granite porphyry (143.6 ± 0.9 Ma), fine-grained granite (142.8 ± 1.1 Ma) and albite granite (141.9 ± 1.3 Ma). The Early Cretaceous granites have geochemical affinities for A-type granites, for example, A/CNK = 0.98–1.07, high TFeO/(TFeO + MgO) ratios, total alkali (Na 2 O + K 2 O), and Ga/Al ratios. The Early Triassic granodiorite have relatively low (87Sr/86Sr) i values of 0.7034–0.7041, whereas the Early Cretaceous granite has slightly variable and higher (87Sr/86Sr) i values, varying from 0.7020 to 0.7065. The Early Triassic granodiorite and Early Cretaceous granites have similar bulk-rock ε Nd (t) values and T DM2 ages, ranging from + 1.89 to + 3.53 and 732 to 845 Ma, respectively. The geochemical data and Sr-Nd isotopes indicate that the Early Cretaceous granites were derived from partial melting of the juvenile middle-upper crust. This study further suggests that the 145.3–141.9 Ma granites are associated with back-arc extension environment during the low-angle subduction of Paleo-Pacific plate. In addition, the whole-rock and zircon compositions show that the Cu-Sn magma is characterized by relatively oxidized and less evolved features compared to the Cu-poor Sn deposits in the region. The rapid increase of oxygen fugacity of the latest episode of the Early Cretaceous magma is supposed to have initiated by the injection of mafic magma, which supported the Cu source for the deposit. Our studies suggest that the Cu-bearing mafic magma/fluid injection plays a key role on the formation of Cu-rich Sn deposit. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ACM was welded on the LLZTO surface as 3D lithiophilic framework. • The molten Li metal wets and spreads on the LLZTO with the assistance of the ACM. • The ACM can also guide the Li metal into an orderly deposition. • A low-cost method is used to observe the interface between Li metal and LLZTO. In this paper an innovative method to improve the contact state between Li metal and LLZTO solid electrolyte surface is presented. Based on the interdiffusion between Cu and Zr elements, the Cu mesh coated with Ag layer (ACM) is welded on the LLZTO ceramic surface at 3 MPa pressure for 30 min at 900 °C under Ar atmosphere. The molten Li metal wets and spreads on the LLZTO solid electrolyte surface with the assistance of the ACM fixed on the ceramic surface. As a result, the interfacial resistance between the Li metal anode and the LLZTO solid electrolyte surface is reduced from 2869.05 Ω·cm2 to 34.1 Ω·cm2. Moreover, the ACM can guide the Li metal into an orderly deposition to enhance the stability of the Li/LLZTO interface. The ACM divides the Li plating/stripping space into several small areas, similar to forming several independent small units in a large system. This division reduces the risk and probability of uneven Li plating/stripping space in the entire system. Therefore, the Li/100ACM-LLZTO /Li symmetric cell can operate stably for 800 h at 0.1 mA/cm2. And the Li/100ACM-LLZTO/LFP full cell still has a capacity retention rate of 81% after 300 cycles at 0.5C. [ABSTRACT FROM AUTHOR]