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991.
Prof. Tong-Xin Liu Xin Wang Shilu Xia Prof. Muqing Chen Mingjie Li Panting Yang Prof. Nana Ma Ziqi Hu Prof. Shangfeng Yang Prof. Guisheng Zhang Prof. Guan-Wu Wang 《Angewandte Chemie (International ed. in English)》2023,62(46):e202313074
Herein, we report divergent additions of 2,2′-diazidobiphenyls to C60 and Sc3N@Ih-C80. In stark contrast to that of the previously reported bis-azide additions, the unexpected cascade reaction leads to the dearomative formation of azafulleroids 2 fused with a 7-6-5-membered ring system in the case of C60. In contrast, the corresponding reaction with Sc3N@Ih-C80 switches to the C−H insertion pathway, thereby resulting in multiple isomers, including a carbazole-derived [6,6]-azametallofulleroid 3 and a [5,6]-azametallofulleroid 4 and an unusual 1,2,3,6-tetrahydropyrrolo[3,2-c]carbazole-derived metallofullerene 5 , whose molecular structures have been unambiguously determined by single-crystal X-ray diffraction analyses. Among them, the addition type of 5 is observed for the first time in all reported additions of azides to fullerenes. Furthermore, unexpected isomerizations from 3 to 5 and from 4 to 5 have been discovered, providing the first examples of the isomerization of an azafulleroid to a carbazole-derived fullerene rather than an aziridinofullerene. In particular, the isomerism of the [5,6]-isomer 4 to the [5,6]-isomer 5 is unprecedented in fullerene chemistry, contradicting the present understanding that isomerization generally occurs between [5,6]- and [6,6]-isomers. Control experiments have been carried out to rationalize the reaction mechanism. Furthermore, representative azafulleroids have been applied in organic solar cells, thereby resulting in improved power conversion efficiencies. 相似文献
992.
Jiashen Zhou Lin Zhang Yiran Wang Wenyan Song Yuzhou Huang Yajuan Mu Werner Schmitz Shu-Yu Zhang Houwen Lin Hong-Zhuan Chen Fei Ye Liang Zhang 《Angewandte Chemie (International ed. in English)》2023,62(46):e202313109
The short-chain dehydrogenase/reductase (SDR) superfamily members acyl-ACP reductases FabG and FabI are indispensable core enzymatic modules and catalytic orientation controllers in type-II fatty acid biosynthesis. Herein, we report their distinct substrate allosteric recognition and enantioselective reduction mechanisms. FabG achieves allosteric regulation of ACP and NADPH through ACP binding across two adjacent FabG monomers, while FabI follows an irreversible compulsory order of substrate binding in that NADH binding must precede that of ACP on a discrete FabI monomer. Moreover, FabG and FabI utilize a backdoor residue Phe187 or a “rheostat” α8 helix for acyl chain length selection, and their corresponding triad residues Ser142 or Tyr145 recognize the keto- or enoyl-acyl substrates, respectively, facilitating initiation of nucleophilic attack by NAD(P)H. The other two triad residues (Tyr and Lys) mediate subsequent proton transfer and (R)-3-hydroxyacyl- or saturated acyl-ACP production. 相似文献
993.
Chuntao Wang Rui Wu Kai Chen Prof. Dr. Shifa Zhu 《Angewandte Chemie (International ed. in English)》2023,62(29):e202305864
Chiral biscyclopropanes are an important skeleton in many bioactive molecules. However, there are few routes to synthesize these molecules with high stereoselectivity due to the nature of multiple stereocenters. Herein, we report the first example of Rh2(II)-catalyzed enantioselective synthesis of bicyclopropanes with alkynes as dicarbene equivalents. The bicyclopropanes with 4–5 vicinal stereocenters and 2–3 all-carbon quaternary centers were constructed in excellent stereoselectivity. This protocol features high efficiency and excellent functional group tolerance. Moreover, the protocol was also extended to the cascaded cyclopropanation/cyclopropenation with excellent stereoselectivities. In these processes, both sp-carbons of alkyne were converted into stereogenic sp3-carbons. Experimental and density functional theory (DFT) calculations revealed that the cooperative weak hydrogen bonds between the substrates and the dirhodium catalyst may play key roles in this reaction. 相似文献
994.
Qingbin Li Yihan Zhang Junfeng Lin Ye Zou Pu Wang Dr. Zhengsheng Qin Yongshuai Wang Dr. Yang Li Prof. Dr. Yu Zhang Dr. Can Gao Prof. Dr. Yaping Zang Prof. Dr. Wenping Hu Prof. Dr. Huanli Dong 《Angewandte Chemie (International ed. in English)》2023,62(42):e202308146
The development of blue-emissive ambipolar organic semiconductor is an arduous target due to the large energy gap, but is an indispensable part for electroluminescent device, especially for the transformative display technology of simple-structured organic light-emitting transistor (SS-OLET). Herein, we designed and synthesized two new dibenzothiophene sulfone-based high mobility blue-emissive organic semiconductors (DNaDBSOs), which demonstrate superior optical property with solid-state photoluminescent quantum yield of 46–67 % and typical ambipolar-transporting properties in SS-OLETs with symmetric gold electrodes. Comprehensive experimental and theoretical characterizations reveal the natural of ambipolar property for such blue-emissive DNaDBSOs-based materials is ascribed to a synergistic effect on lowering LUMO level and reduced electron injection barrier induced by the interfacial dipoles effect on gold electrodes due to the incorporation of appropriate DBSO unit. Finally, efficient electroluminescence properties with high-quality blue emission (CIE (0.179, 0.119)) and a narrow full-width at half-maximum of 48 nm are achieved for DNaDBSO-based SS-OLET, showing good spatial control of the recombination zone in conducting channel. This work provides a new avenue for designing ambipolar emissive organic semiconductors by incorporating the synergistic effect of energy level regulation and molecular-metal interaction, which would advance the development of superior optoelectronic materials and their high-density integrated optoelectronic devices and circuits. 相似文献
995.
Yun-Cheng Luo Ming-Kuan Wang Ling-Chao Yu Prof. Dr. Xingang Zhang 《Angewandte Chemie (International ed. in English)》2023,62(37):e202308690
The selective transition-metal catalyzed C−F bond functionalization of inexpensive industrial fluorochemicals represents one of the most attractive approaches to valuable fluorinated compounds. However, the selective C(sp2)−F bond carbofunctionalization of refrigerant hydrofluoroolefins (HFOs) remains challenging. Here, we report a nickel-catalyzed selective C(sp2)−F bond alkylation of HFO-1234yf with alkylzinc reagents. The resulting 2-trifluoromethylalkenes can serve as a versatile synthon for diversified transformations, including the anti-Markovnikov type hydroalkylation and the synthesis of bioactive molecule analogues. Mechanistic studies reveal that lithium salt is essential to promote the oxidative addition of Ni0(Ln) to the C−F bond; the less electron-rich N-based ligands, such as bipyridine and pyridine-oxazoline, feature comparable or even higher oxidative addition rates than the electron-rich phosphine ligands; the strong σ-donating phosphine ligands, such as PMe3, are detrimental to transmetallation, but the less electron-rich and bulky N-based ligands, such as pyridine-oxazoline, facilitate transmetallation and reductive elimination to form the final product. 相似文献
996.
ChangYan Hu Dr. Ying Li Dr. Dong Wang Dr. Chunjin Wu Feng Chen Linghong Zhang Prof. Fang Wan Prof. Weibo Hua Prof. Yan Sun Prof. Benhe Zhong Dr. Zhenguo Wu Prof. Xiaodong Guo 《Angewandte Chemie (International ed. in English)》2023,62(46):e202312310
Na2Ti6O13 (NTO) with high safety has been regarded as a promising anode candidate for sodium-ion batteries. In the present study, integrated modification of migration channels broadening, charge density re-distribution, and oxygen vacancies regulation are realized in case of Nb-doping and have obtained significantly enhanced cycling performance with 92 % reversible capacity retained after 3000 cycles at 3000 mA g−1. Moreover, unexpected low-temperature performance with a high discharge capacity of 143 mAh g−1 at 100 mA g−1 under −15 °C is also achieved in the full cell. Theoretical investigation suggests that Nb preferentially replaces Ti3 sites, which effectively improves structural stability and lowers the diffusion energy barrier. What's more important, both the in situ X-ray diffraction (XRD) and in situ Raman furtherly confirm the robust spring effect of the Ti−O bond, making special charge compensation mechanism and respective regulation strategy to conquer the sluggish transport kinetics and low conductivity, which plays a key role in promoting electrochemical performance. 相似文献
997.
Dr. Xuelin Yao Dr. Heng Zhang Fanmiao Kong Dr. Antoine Hinaut Dr. Rémy Pawlak Prof. Dr. Masanari Okuno Dr. Robert Graf Dr. Peter N. Horton Prof. Dr. Simon J. Coles Prof. Dr. Ernst Meyer Prof. Dr. Lapo Bogani Prof. Dr. Mischa Bonn Prof. Dr. Hai I. Wang Prof. Dr. Klaus Müllen Prof. Dr. Akimitsu Narita 《Angewandte Chemie (International ed. in English)》2023,62(46):e202312610
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
998.
Prof. Xiaona Li Yang Xu Prof. Changtai Zhao Duojie Wu Dr. Limin Wang Matthew Zheng Xu Han Dr. Simeng Zhang Junyi Yue Prof. Biwei Xiao Dr. Wei Xiao Dr. Ligen Wang Prof. Tao Mei Prof. Meng Gu Prof. Jianwen Liang Prof. Xueliang Sun 《Angewandte Chemie (International ed. in English)》2023,62(48):e202306433
As exciting candidates for next-generation energy storage, all-solid-state lithium batteries (ASSLBs) are highly dependent on advanced solid-state electrolytes (SSEs). Here, using cost-effective LaCl3 and CeCl3 lattice (UCl3-type structure) as the host and further combined with a multiple-cation mixed strategy, we report a series of UCl3-type SSEs with high room-temperature ionic conductivities over 10−3 S cm−1 and good compatibility with high-voltage oxide cathodes. The intrinsic large-size hexagonal one-dimensional channels and highly disordered amorphous phase induced by multi-metal cation species are believed to trigger fast multiple ionic conductions of Li+, Na+, K+, Cu+, and Ag+. The UCl3-type SSEs enable a stable prototype ASSLB capable of over 3000 cycles and high reversibility at −30 °C. Further exploration of the brand-new multiple-cation mixed chlorides is likely to lead to the development of advanced halide SSEs suitable for ASSLBs with high energy density. 相似文献
999.
Jiahui Zeng Yu Fu Yue Wu Shanshan Wang Wenxiang Zhang Prof. Heping Ma 《Angewandte Chemie (International ed. in English)》2023,62(42):e202310235
Xe is an ideal anesthetic gas, but it has not been widely used in practice due to its high cost and low output. Closed-circuit Xe recovery and recycling is an economically viable method to ensure adequate supply in medical use. Herein, we design an innovative way to recover Xe by using a stable fluorinated metal-organic framework (MOF) NbOFFIVE-1-Ni to eliminate CO2 from moist exhaled anesthetic gases. Unlike other Xe recovery MOFs with low Xe/CO2 selectivity (less than 10), NbOFFIVE-1-Ni could achieve absolute molecular sieve separation of CO2/Xe with excellent CO2 selectivity (825). Mixed-gas breakthrough experiments assert the potential of NbOFFIVE-1-Ni as a molecular sieve adsorbent for the effective and energy-efficient removal of carbon dioxide with 99.16 % Xe recovery. Absolute CO2/Xe separation in NbOFFIVE-1-Ni makes closed-circuit Xe recovery and recycling can be easily realized, demonstrating the potential of NbOFFIVE-1-Ni for important anesthetic gas regeneration under ambient conditions. 相似文献
1000.
Tiantian Wu Hong Wang Run Tian Shuang Guo Yuhui Liao Prof. Jianbing Liu Prof. Baoquan Ding 《Angewandte Chemie (International ed. in English)》2023,62(46):e202311698
Bacteria infection is a significant obstacle in the clinical treatment of exposed wounds facing widespread pathogens. Herein, we report a DNA origami-based bactericide for efficient anti-infection therapy of infected wounds in vivo. In our design, abundant DNAzymes (G4/hemin) can be precisely organized on the DNA origami for controllable generation of reactive oxygen species (ROS) to break bacterial membranes. After the destruction of the membrane, broad-spectrum antibiotic levofloxacin (LEV, loaded in the DNA origami through interaction with DNA duplex) can be easily delivered into the bacteria for successful sterilization. With the incorporation of DNA aptamer targeting bacterial peptidoglycan, the DNA origami-based bactericide can achieve targeted and combined antibacterial therapy for efficiently promoting the healing of infected wounds. This tailored DNA origami-based nanoplatform provides a new strategy for the treatment of infectious diseases in vivo. 相似文献