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81.
Structurally defined graphene nanoribbons (GNRs) have emerged as promising candidates for nanoelectronic devices. Low band gap (<1 eV) GNRs are particularly important when considering the Schottky barrier in device performance. Here, we demonstrate the first solution synthesis of 8-AGNRs through a carefully designed arylated polynaphthalene precursor. The efficiency of the oxidative cyclodehydrogenation of the tailor-made polymer precursor into 8-AGNRs was validated by FT-IR, Raman, and UV/Vis-near-infrared (NIR) absorption spectroscopy, and further supported by the synthesis of naphtho[1,2,3,4-ghi]perylene derivatives ( 1 and 2 ) as subunits of 8-AGNR , with a width of 0.86 nm as suggested by the X-ray single crystal analysis. Low-temperature scanning tunneling microscopy (STM) and solid-state NMR analyses provided further structural support for 8-AGNR . The resulting 8-AGNR exhibited a remarkable NIR absorption extending up to ∼2400 nm, corresponding to an optical band gap as low as ∼0.52 eV. Moreover, optical-pump TeraHertz-probe spectroscopy revealed charge-carrier mobility in the dc limit of ∼270 cm2 V−1 s−1 for the 8-AGNR .  相似文献   
82.
Owing to high modularity and synthetic tunability, metal–organic frameworks (MOFs) on textiles are poised to contribute to the development of state-of-the-art wearable systems with multifunctional performance. While these composite materials have demonstrated promising functions in sensing, filtration, detoxification, and biomedicine, their applicability in multifunctional systems is only beginning to materialize. This review highlights the multifunctionality and versatility of MOF-integrated textile systems. It summarizes the operational goals of MOF@textile composites, encompassing sensing, filtration, detoxification, drug delivery, UV protection, and photocatalysis. Building upon these recent advances, this review concludes with an outlook on emerging opportunities for the diverse applications of MOF@textile systems in the realm of smart wearables.  相似文献   
83.
Covalent adaptable networks (CANs) possess unique properties as a result of their internal dynamic bonds, such as self-healing and reprocessing abilities. In this study, we report a thermally responsive C−Se dynamic covalent chemistry (DCC) that relies on the transalkylation exchange between selenonium salts and selenides, which undergo a fast transalkylation reaction in the absence of any catalyst. Additionally, we demonstrate the presence of a dissociative mechanism in the absence of selenide groups. After incorporation of this DCC into selenide-containing polymer materials, it was observed that the cross-linked networks display varying dynamic exchange rates when using different alkylation reagents, suggesting that the reprocessing capacity of selenide-containing materials can be regulated. Also, by incorporating selenonium salts into polymer materials, we observed that the materials exhibited good healing ability at elevated temperatures as well as excellent solvent resistance at ambient temperature. This novel dynamic covalent chemistry thus provides a straightforward method for the healing and reprocessing of selenide-containing materials.  相似文献   
84.
On-surface synthesis is at the verge of emerging as the method of choice for the generation and visualization of unstable or unconventional molecules, which could not be obtained via traditional synthetic methods. A case in point is the on-surface synthesis of the structurally elusive cyclotriphosphazene (P3N3), an inorganic aromatic analogue of benzene. Here, we report the preparation of this fleetingly existing species on Cu(111) and Au(111) surfaces at 5.2 K through molecular manipulation with unprecedented precision, i.e., voltage pulse-induced sextuple dechlorination of an ultra-small (about 6 Å) hexachlorophosphazene P3N3Cl6 precursor by the tip of a scanning probe microscope. Real-space atomic-level imaging of cyclotriphosphazene reveals its planar D3h-symmetric ring structure. Furthermore, this demasking strategy has been expanded to generate cyclotriphosphazene from a hexaazide precursor P3N21 via a different stimulation method (photolysis) for complementary measurements by matrix isolation infrared and ultraviolet spectroscopy.  相似文献   
85.
The development of PtIV prodrugs that are reduced into the therapeutically active PtII species within the tumor microenvironment has received much research interest. In order to provide spatial and temporal control over the treatment, there is a high demand for the development of compounds that could be selectively activated upon irradiation. Despite recent progress, the majority of PtIV complexes are excited with ultraviolet or blue light, limiting the use of such compounds to superficial application. To overcome this limitation, herein, the first example of PtIV prodrug nanoparticles that could be reduced with deeply penetrating ultrasound radiation is reported, enabling the treatment of deep-seated or large tumors. The nanoparticles were found to selectively accumulate inside a mouse colon carcinoma tumor upon intravenous injection and were able to eradicate the tumor upon exposure to ultrasound radiation.  相似文献   
86.
Graphdiyne (GDY) with a direct band gap, excellent carrier mobility and uniform pores, is regarded as a promising photocatalytic material for solar energy conversion, while the research on GDY in photocatalysis is a less developed field. Herein, the distinctive structure, adjustable band gap, and electronic properties of GDY for photocatalysis is firstly summarized. The construction and progress of GDY-based photocatalysts for solar energy conversion, including H2 evolution reaction (HER), CO2 reduction reaction (CO2RR) and N2 reduction reaction (NRR) are then elaborated. At last, the challenges and perspectives in developing GDY-based photocatalysts for solar fuel production are discussed. It is anticipated that a timely Minireview will be helpful for rapid progress of GDY in solar energy conversion.  相似文献   
87.
An improved five-step synthetic route from l -fucose to an N-glycosyl l -valine methyl ester has been developed. The new route involves glycosidation of l -fucose with phenol in a β-selective manner without protection/deprotection steps and one-pot stereochemical inversion of a secondary alcohol intermediate and is superior to our previous one both in the number of steps and in overall yield. An N-glycosyl l -valine benzyl ester, prepared from l -fucose in an analogous way, has been elaborated into an N-amykitanosyl tetramic acid derivative, Li's synthetic intermediate for amycolamicin, via a four-step sequence which features the utilization of Bestmann's ylide to stereoconvergently construct an N-glycosyl tetramic acid intermediate in a single step, opening of a cyclic carbonate ring with an amine to regioselectively install a carbamate functionality, and visible light-mediated oxidative debenzylation of an N,N-dibenzyl carbamate.  相似文献   
88.
We report the development of a metal-free four-step one-pot synthetic strategy to access high-value functionalized phthalazines using o-methyl benzophenones as starting compounds. Combining a light-mediated enolization of o-methyl benzophenones/Diels-Alder reaction domino process with a subsequent deprotection/aromatization domino reaction in one-pot leads to sustainable and efficient organic synthesis. The tangible advantages, i. e., absence of catalysts or additives, utilization of commercially available and/or easily accessible substrates, mild reaction conditions, simplicity, and single work-up procedure, make this combined process highly appealing for the direct construction of various 1-aryl-phthalazines. Importantly, in vitro bioactivity evaluation of these newly prepared heterocyclic compounds demonstrated a strong antiviral efficacy against major human pathogens like HCMV and SARS-CoV-2.  相似文献   
89.
Substituted pyrroles are prevalent aromatic ring systems encountered in numerous natural products and bioactive molecules. Herein, a novel ynamide scaffold has been designed, synthesized and subsequently applied to an unprecedented gold-catalyzed and para-toluenesulfonic acid (PTSA)-assisted cascade cycloisomerization reaction for the synthesis of β-pyrrole substituted α,β-unsaturated ketones. Notably, the reaction is stereoselective, offering E-isomer as major product with low to moderate yield.  相似文献   
90.
The efficient three-component cascade coupling reaction of 3-haloisoquinolines, haloalkanes, and sp3-carbon nucleophiles (acetophenone or nitromethane) led to a series of structurally novel 1,2-disubstituted-3-isoquinolinones through the formation of C(sp3)−C(sp2), C−N, and C=O bonds. The NaOAc-promoted reaction described in this work is simple to operate, environment friendly, and highly selective.  相似文献   
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