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201.
202.
Jianmin Wang Liang Yan Guang Qian Gaomeng Lv Guixian Li Jishuan Suo Xiaolai Wang 《Reaction Kinetics and Catalysis Letters》2007,91(1):111-118
The pyridine-heteropoly compounds are very active catalysts for phenol hydroxylation to dihydroxybenzenes with hydrogen peroxide
as oxidant in aqueous solutions. The conversion of phenol reaches 77.8%, and the selectivity for dihydroxybenzenes reaches
99%. 相似文献
203.
A. Valtz 《Thermochimica Acta》2006,443(2):245-250
Specially designed equipment based on a static-analytic method with Rolsi™ pneumatic samplers for on line gas chromatograph analysis has been used for this work. Operating pressures and temperatures are between 0.3 and 10 MPa and between 293 and 393 K. Vapor pressures over liquid-liquid mixtures and benzene solubility data are reported herein for benzene with amine aqueous solutions (methyldiethanolamine (MDEA) and diglycolamine (DGA)). Modelling of solubility data is achieved using a simple model based on activity coefficients. 相似文献
204.
Christoph Loenarz 《Angewandte Chemie (International ed. in English)》2020,59(10):3776-3780
The 2019 Nobel Prize in Physiology or Medicine honours three scientists that devoted their careers to pursuing an audacious basic science question: by what mechanisms do animals sense oxygen, and how can cells adapt to a lack of oxygen? The identification of the human hypoxia inducible factor pathway has enabled new approaches for the therapy of related diseases including cancer, cardiovascular disease, anaemia, and stroke. The intricate molecular details of oxygen sensing broadened interest in the family of iron‐ and 2‐oxoglutarate‐dependent oxygenases known from elaborate natural product chemistry, and catalysed major progress in macromolecule hydroxylation. The laureates’ work enables numerous avenues for molecular scientists, from C?H activation chemistry to PROTAC technology, medicinal chemistry, and epigenetics. 相似文献
205.
FeOx/HZSM-5 catalyst with 8 wt.%Fe-loading(8-FeZ) exhibited significantly higher reactivity in the benzylation of benzene with benzyl chloride than FeOx/HZSM-5 catalyst with 2.5 wt.%Fe-loading(2.5-FeZ) because the synergistic catalysis between isolated Fe3+ and superfine Fe2O3 occurred on 8-FeZ in the reaction. 相似文献
206.
Asuka Nishikawa Shintaro Saito Yuichi Hashimoto Kenji Koga Ryuichi Shirai 《Tetrahedron letters》2001,42(52)
Efficient synthesis of l-α-phosphatidyl-d-myo-inositol 3,5-bisphosphate was achieved from 1,2,5,6-diisopropylidene-d-glucose by utilizing ring-closing metathesis and catalytic OsO4 dihydroxylation. 相似文献
207.
James E. Atwater 《Reaction Kinetics and Catalysis Letters》2000,71(2):319-323
Aqueous phase heterogeneous catalytic oxidation of benzene by dissolved oxygen is reported. Using a bimetallic platinum-ruthenium catalyst supported on a high surface area activated carbon, good conversions were obtained at temperatures above 100°C and space-times greater than 40 seconds. Complete conversion of benzene to carbon dioxide and water was achieved at 100°C with a reactor space-time of 300 s. 相似文献
208.
209.
Antimicrobial properties casing wide applicability in water detoxification, pharmaceutics and in industries. Present work focus on the synthesis of a new series of Schiff Bases (E)-4-(1 substituted-1H Benzo[d]imidazole-2-yl)-N'-(substituted Benzylidene)benzohydrazide (5a-5l) were synthesized. The convenient route for the synthesis of new analogues by the condensation of 4-(substituted -1H-Benzo[d]imidazole-2-yl)-N'- Hydrazine with different derivatives of aromatic aldehydes were described using different solvents and catalysts. The structures of the synthesized compounds were ascertain by spectral techniques viz. IR, 1H NMR, MS and Physical Elemental data. Compounds were also subjected to thermal analysis to study their physical and chemical properties. The title compounds were also screened for their antimicrobial activity against various bacterial & Fungal strains. Results of bioassay vary with diverse group attached to Benzimdazole motif and could be helpful for the development of other bioactive molecules. 相似文献
210.
C—H键的活化是有机合成中最重要的科学问题之一。以环境友好的双氧水或者氧气为氧化剂的苯羟基化制备苯酚的反应,不仅涉及苯环的$\text C_{\text s \text p^{2}}— \text H $活化这一基础问题,还涉及双氧水或氧气的活化,以及双氧水的分解、苯酚的深度氧化等副反应,几十年来一直是有机合成领域的一大挑战。更重要的是,在大力倡导绿色化工的背景之下,该反应愈加受到工业界的青睐,期望它能够取代异丙苯法成为苯酚生产的绿色新工艺。本文以苯羟基化制备苯酚的催化反应机理为线索,综述近年来金属基催化剂以及处于起步阶段的非金属催化剂的最新研究进展,着重从自由基机理和非自由基机理两个方面详细归纳分析催化剂的组成结构与其反应的活性和选择性之间的构效关系,并就该领域未来的发展动向及需要关注的问题给出了展望和建议,期望有助于深化对催化机理的认识,并为进一步研发更高活性和稳定性的苯羟基化催化剂提供有益借鉴。
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