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31.
Fangyuan Zhou Lesong Li Kao Lin Feng Zhang Prof. Dr. Guo-Jun Deng Dr. Hang Gong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(19):4246-4250
The radical–radical coupling reaction is an important synthetic strategy. In this study, the iron-catalyzed radical–radical cross-coupling reaction based on the decarboxylation of keto acids and decarbonylation of aliphatic aldehydes to obtain valuable aryl ketones is reported for the first time. Remarkably, when tertiary aldehydes were used as carbonyl sources, ketone esters were selectively obtained instead of ketones. The gram-scale preparation of aryl ketone through this strategy was easily achieved by using only 3 mol % of the iron catalyst. As a proof-of-concept, the bioactive molecule flurprimidol was synthesized in two steps by using this strategy. 相似文献
32.
Dr. Jinghui Zhang Lei Gong Xiaoshuang Zhang Dr. Mengliang Zhu Chaorui Su Qing Ma Dr. Dongdong Qi Prof. Yongzhong Bian Prof. Hongwu Du Prof. Jianzhuang Jiang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(61):13842-13848
Two-photon excited fluorescent (TPEF) materials are highly desirable for bioimaging applications owing to their unique characteristics of deep-tissue penetration and high spatiotemporal resolution. Herein, by connecting one, two, or three electron-deficient zinc porphyrin units to an electron-rich triazatruxene core via ethynyl π-bridges, conjugated multipolar molecules TAT-(ZnP) n (n=1–3) were developed as TPEF materials for cell imaging. The three new dyes present high fluorescence quantum yields (0.40–0.47) and rationally improved two-photon absorption (TPA) properties. In particular, the peak TPA cross section of TAT-ZnP (436 GM) is significantly larger than that of the ZnP reference (59 GM). The δTPA values of TAT-(ZnP)2 and TAT-(ZnP)3 further increase to 1031 and up to 1496 GM, respectively, indicating the effect of incorporated ZnP units on the TPA properties. The substantial improvement of the TPEF properties is attributed to the formation of π-conjugated quadrapole/octupole molecules and the extension of D -π-A-D systems, which has been rationalized by density function theory (DFT) calculations. Moreover, all of the three new dyes display good biocompatibility and preferential targeting ability toward cytomembrane, thus can be superior candidates for TPEF imaging of living cells. Overall, this work demonstrated a promising strategy for the development of porphyrin-based TPEF materials by the construction and extension of D -π-A-D multipolar array. 相似文献
33.
Tianyu Gong Longhai Guo Jun Ye Lifan He Teng Qiu Xiaoyu Li 《Journal of polymer science. Part A, Polymer chemistry》2021,59(16):1807-1820
The implementation of covalent adaptable networks (CANs) in general resin system is becoming attractive. In this work, we propose a simple post-curing strategy based on the core-shell structured acrylate latex for the achievement on both the improved general performance and the CANs characteristics in latex films. The building to the CANs was relied on the introduction of 4,4′-diaminophenyl disulfide as the curing agent, which cured the acetoacetoxy decorated shell polymer through the ketoamine reaction. The metathesis reaction of aromatic disulfides in the crosslinking segments enabled the thermally induced dynamic behavior of the network as revealed in the stress relaxation tests by comparison with other diamine crosslinking agents without the incorporation of disulfide. The synergism of the dynamic crosslinking of the shell polymer and static crosslinking in the core polymer contributed to the improved mechanical strength (15 MPa, strain% = 250%) and the suppressed water adsorption (~1% in 24 h of soaking) of the latex film, which exhibited above 90% of recovery in both strength and strain from a cut-off film damage within 1 h at 80°C. Moreover, the cured latex film could be recycled, and 75% of the mechanical performance was regained after three fragmentation-hot-pressing cycles. These, in addition with the feasible and environmental friendly characteristics, suggest a sustainable paradigm toward the smart thermosetting latex polymers. 相似文献
34.
Yao Yuan Chen Ying Chen Jianyong Gong Yulie 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2357-2367
Journal of Thermal Analysis and Calorimetry - Based on innovative design, a liquid–vapor separation plate condenser with excellent heat transfer performance is invented. It takes less time to... 相似文献
35.
Huaizhi Gao Runnan Yu Zongwen Ma Yongshuai Gong Biao Zhao Qianglong Lv Zhan'ao Tan 《Journal of polymer science. Part A, Polymer chemistry》2022,60(6):865-916
Organometallic complexes (OMCs) consisting of organic and metal active moieties have shown immense potential for application in solar cells. The diverse structure, rich porosity, and unique charge centers of OMCs enable them to be functional in solar cells. In this review, we introduced four types of OMCs, such as crown organometallic complexes, β-diketone metal complexes, cyclometallic complexes, and main chain metal-containing polymers, providing an in-depth analysis of the structure-performance relationship. OMCs could serve as active or interlayer materials in a variety of solar cell systems such as organic solar cells, perovskite solar cells, and dye-sensitized solar cells, especially some metals to improve the photoelectric performance of the device as dopants. In the end, perspectives on the opportunities and challenges of OMCs are given. 相似文献
36.
Haicun Yang Shuipi Cai Yu Jiang Zheng Cao Wenzhong Ma Fanghong Gong Guoliang Tao Chunlin Liu 《Journal of polymer science. Part A, Polymer chemistry》2022,60(10):1571-1587
The commonly used multi-center initiation methods always lead to the formation of quantities of homopolymer in the surface tailoring based on reverse atom transfer radical polymerization (ATRP) and reversible addition-fragmentation chain-transfer (RAFT) polymerization. In this study, a monocenter redox pair constructed of silica bearing tert-butyl hydroperoxide groups and ascorbic acid (SiO2-TBHP/AsAc) was applied to substitute the commonly used initiation method of R-supported RAFT grafting polymerization. All the propagating radicals were restricted on the surface of solid particles during the whole procedure theoretically, resulting in a higher grafting efficiency of 95.1% combined with the “controllable” feature at 10 h. This redox pair was also used to initiate the reverse ATRP in miniemulsion successfully with a grafting efficiency of 86.3% at 10 h. The grafting efficiency obtained under this monocenter initiation method was significantly higher than that of the frequently reported surface modification by reverse ATRP and RAFT polymerization. In addition, the high-efficient surface tailoring was traced and confirmed by nuclear magnetic resonance, Fourier transform infrared, X-ray photoelectron spectroscopy, thermogravimetric analysis, transmission electron microscopy, and other analysis tests. The advantage of this monocenter redox pair will open a new avenue for the potential “high-efficient” surface tailoring of various materials. 相似文献
37.
Yong Gao Dani Zhang Dr. Jingjing Li Prof. Hao Gong Dr. Cheng Jiang Dr. Hairong Xue Prof. Xianli Huang Prof. Tao Wang Prof. Jianping He 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(71):e202202410
Electrocatalysis is the most promising strategy to generate clean energy H2, and the development of catalysts with excellent hydrogen evolution reaction (HER) performance at high current density that can resist strong alkaline and acidic electrolyte environment is of great significance for practical industrial application. Therefore, a P doped MoS2@Ni3S2 nanorods array (named P-NiMoS) was successfully synthesized through successive sulfuration and phosphorization. P-NiMoS presents a core/shell structure with a heterojunction between MoS2 (shell) and Ni3S2 (core). Furthermore, the doping of P modulates the electronic structure of the P-NiMoS; the electrons transfer from the t2g orbital of Ni element to the eg empty orbital of Mo element through the Ni−S−Mo bond at the Ni3S2 and MoS2 heterojunction, facilitating the hydrogen evolution reaction. As a result, P-NiMoS exhibits excellent HER activity; the overpotential is 290 mV at high current density of 250 mA cm−2 in alkaline electrolyte, which is close to Pt/C (282 mV@250 mA cm−2), and P-NiMoS can stably evolve hydrogen for 48 h. 相似文献
38.
39.
Cong Yu Zhengdong Guo Lifeng Yang Jiyu Cui Sen Chen Yawen Bo Xian Suo Qihan Gong Shang Zhang Prof. Xili Cui Shengbao He Prof. Huabin Xing 《Angewandte Chemie (International ed. in English)》2023,62(16):e202218027
Adsorptive separation is an energy-efficient alternative, but its advancement has been hindered by the challenge of industrially potential adsorbents development. Herein, a novel ultra-microporous metal-organic framework ZU-901 is designed that satisfies the basic criteria raised by ethylene/ethane (C2H4/C2H6) pressure swing adsorption (PSA). ZU-901 exhibits an “S” shaped C2H4 curve with high sorbent selection parameter (65) and could be mildly regenerated. Through green aqueous-phase synthesis, ZU-901 is easily scalable with 99 % yield, and it is stable in water, acid, basic solutions and cycling breakthrough experiments. Polymer-grade C2H4 (99.51 %) could be obtained via a simulating two-bed PSA process, and the corresponding energy consumption is only 1/10 of that of simulating cryogenic distillation. Our work has demonstrated the great potential of pore engineering in designing porous materials with desired adsorption and desorption behavior to implement an efficient PSA process. 相似文献
40.
Dr. Yuxuan Hu Dr. Jingsheng Miao Dr. Cheng Zhong Yang Zeng Prof. Shaolong Gong Dr. Xiaosong Cao Xue Zhou Dr. Yu Gu Prof. Chuluo Yang 《Angewandte Chemie (International ed. in English)》2023,62(19):e202302478
Heavy-atom integration into thermally activated delayed fluorescence (TADF) molecule could significantly promote the reverse intersystem crossing (RISC) process. However, simultaneously achieving high efficiency, small roll-off, narrowband emission and good operational lifetime remains a big challenge for the corresponding organic light-emitting diodes (OLEDs). Herein, we report a pure green multi-resonance TADF molecule BN-STO by introducing a peripheral heavy atom selenium onto the parent BN-Cz molecule. The organic light-emitting diode device based on BN-STO exhibited state-of-the-art performance with a maximum external quantum efficiency (EQE) of 40.1 %, power efficiency (PE) of 176.9 lm W−1, well-suppressed efficiency roll-off and pure green gamut. This work reveals a feasible strategy to reach a balance between fast RISC process and narrow full width at half maximum (FWHM) of MR-TADF by heavy atom effect. 相似文献