JOURNAL OF CATALYSIS
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2021
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IF 7.92
L.J. Zhang,J.C. Yuan,L.J. Ma,Z.Y. Tang,X.M. Zhang
Zirconium-based porphyrinic MOFs (PMOFs, MOF = metal-organic framework) have gained considerable attention in the field of electric/thermo/photo-catalysis as heterogeneous single-site catalysts; however, the study on multisite synergistic catalysis of PMOFs are rare. Herein, we have successfully developed a highly regio- and stereo-selective synthetic method of ( E )- β -vinylboronates through hydroboration of alkynes using PCN-222 (Cu, PCN = porous coordination network) as multifunctional heterogeneous catalyst. Compared with homogeneous catalytic system, high TOF value is achieved in the developed method, originating from the synergistic effect of central Cu(II) ions, N atoms of porphyrin rings and terminal –OH groups on Zr-nodes. Notably, density functional theory (DFT) study reveals that five-membered “Cu-N-B-C-C” ring is the key species responsible for the hydroboration process with specific selectivity.
研究领域:
化学
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材料科学
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催化反应
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DOI
高影响因子
MOLECULES
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2022
·Vol. 27
·期 22
·7962
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IF 4.927
Shuhan Chen,Wei Wen,Xue Zhao,Zelang Zhang,Weishuang Li,Yaoyao Zhang,Bojie Li,Lei Zhu
Here, we describe the preparation of copper nanoparticles that are stabilized on a chitosan composite film (CP@Cu). This material could catalyze the 1,6-hydroboration reactions ofp-quinone methides with B2pin2as a boron source under mild conditions. This reaction exhibited very good functional group compatibility, and the organoboron compounds that were formed could easily be converted into corresponding hydroxyl products with good to excellent yields. This newly developed methodology provides an efficient and sequential pathway for the synthesis ofgem-disubstituted methanols.Keywords:copper nanoparticles;chitosan composite film;hydroboration reactions;p-quinone methides;organoboron compounds
研究领域:
化学
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材料科学
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有机合成
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
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IF 9.4
Long Tian,Xiaonan Song,Yi Liu,Churu Zhang,Lan Shi,Qinglin Chen,Yanyan Deng,Weigang Cui,Shaoyun Shan,Tianding Hu
Defect-engineered metal–organic frameworks (DEMOFs) are emerging advanced materials. The construction of DEMOFs is of great significance; however, DEMOF-based catalysis remains unexplored. (E)-vinylboronates, an important building block for asymmetric synthesis, can be synthesized via the hydroboration of alkynes. However, the lack of high-performance catalysts considerably hinders their synthesis. Herein, a series of DEHKUST-1 (HKUST = Hong Kong University of Science and Technology) (Da–f) catalysts with missing occupation of linkers at Cu nodes were designed by partially replacing benzene-1,3,5-tricarboxylate (H 3 BTC) with defective connectors of pyridine-3,5-dicarboxylate (PYDC) to efficiently promote the hydroboration of alkynes. Results showed that the Dd containing 0.8 doping ratio of PYDC exhibited remarkable catalytic activity than the defect-free HKUST-1. This originated from the improved accessibility for reactants towards the Lewis acid active Cu sites of DEHKUST-1 due to the presence of plenty of rooms next to the Cu sites and enhanced coordination ability in such ‘defective’ HKUST-1. Dd had high selectivity (>99 %) and yield (>96 %) for (E)-vinylboronates and extensive functional group compatibility for terminal alkynes. Density functional theory (DFT) calculations were performed to elucidate the mechanism of hydroboration. Compared with that of defect-free HKUST-1, the low energy barrier of DEHKUST-1 can be attributed to the lower coordination number of Cu sites and enhanced accessibility of Cu active sites towards reagents.
研究领域:
材料科学
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催化
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化学工程
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理论化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
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2023
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IF 3.6
Ming Huang,Changsheng Zhou,Ke-Fang Yang,Ze Li,Guo-Qiao Lai,Pinglu Zhang
An effective (NHC)AgCl catalysis was developed in the hydroborylation of cyclopropenes with B2pin2, delivering a variety of cyclopylboronates in a stereoselective manner, which could be easily transformed for the construction of versatile cyclopropanes. This protocol works effectively under mild reaction conditions in an open-air atmosphere, and it was easy to apply on a gram scale. This novel method in detail was also explored by control experiments, providing a number of key insights. The kinetic process followed by 1H NMR indicated that the reaction was finished in 15 min. Furthermore, the mechanism of silver(I)-catalyzed hydroborylation of cyclopropenes was proposed, with the protonation by methanol as the rate-determining step.
研究领域:
有机化学
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催化
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合成化学
✓ 已验证
DOI
PubMed
高影响因子