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891.
One novel complex [Ni(phen)3]·(C8H12O4)·(H2O)14 with hexane dicarboxylic acid and 1,10-phenanthroline has been hydrothermally synthesized and characterized. Crystal data: monoclinic, space group C2/c, a = 2.3475(5), b = 1.2208(2), c = 1.9499(4) nm, β = 114.682(3)o, V = 5.0778(16) nm3, Dc = 1.339 g/cm3, Z = 4, μ(MoKα) = 0.458 mm-1, F(000) = 2168, GOOF = 1.014, R = 0.0401 and wR = 0.0961. The nickel(Ⅱ) center in the title complex is coordinated with six nitrogen atoms of three 1,10-phenanthroline molecules, giving a distorted octahedral coordination geometry. However, the nickel(Ⅱ) ion does not coordinate to the hexane dicarboxylic acid. The complex molecules form a 3D structure through hydrogen bonds. TG analysis shows that the title complex is stable below 240.0 ℃. 相似文献
892.
Selvaraj Munirasu Ashwini Deshpande Durairaj Baskaran 《Macromolecular rapid communications》2008,29(18):1538-1543
A simple method has been described to remove catalyst from the copper mediated atom transfer radical polymerization (ATRP) of benzyl methacrylate and methyl methacrylate in anisole at 25 °C using hydrated natural clay (sodium montmorillonite, Na‐clay). The method consists of (1) addition of hydrated clay (CuI/clay ≈ 5 wt.‐%) either during or after the polymerization, (2) oxidation of catalyst complex by exposing the terminated reaction mixture in air, and (3) filtration to obtain catalyst free polymer solution. A strong coordination of CuBr‐ligand complex onto hydrated clay (10 wt.‐% < H2O/clay < 30 wt.‐%) upon oxidation resulted in polymers with no or insignificant residual catalyst (<1.74 ppm), as determined by UV‐vis and atomic absorption spectroscopy. The recovered clay exhibited expanded intercalary layers and absence of polymer within it.
893.
Yu Huilan Dong Junjun Hu Zhen Pei Chengxin Liu Shilei Xiang Yu 《Phosphorus, sulfur, and silicon and the related elements》2016,191(1):111-116
A new method for the synthesis of organophosphorylated adducts of the nonapeptide FGESAGAAS is presented. The adducts were obtained by using sarin (GB) or soman (GD) as the organophosphorylating reagents and cesium carbonate as the acid scavenger. Greater than 50% of the peptide was modified on serine 4. MS/MS spectra acquired on an Agilent 6520 quadrupole time of flight mass spectrometer demonstrated that serine 4, but not serine 9 in the nonapeptide, was modified. The adducts included the characteristic isopropyl group of sarin and the pinacolyl group of soman, indicating that aging had not occurred. It was concluded that the new synthetic method yielded sarin and soman-modified peptides that could be used as references when analyzing human exposure to these nerve agents. 相似文献
894.
The chiral molecule (+)-N-[(3S)-3-(4-fluorophenyl)heptanoyl]bornane-10,2-sultam (C23H32FNO3S, Mr = 421.56), a fluorine-containing derivative of camphorsultam, was conveniently obtained and crystallized in the orthorhombic space group P212121 with a = 7.9044(11), b = 11.6680(16), c = 24.899(3) , V = 2296.4(5) 3, Z = 4, Dc = 1.219 Mg/m3, λ = 0.71073 , μ(MoKα) = 0.172 mm-1 and F(000) = 904. X-ray diffraction analysis reveals that the six-membered ring of sultam shows a boat conformation (Fig. 1). The planes constructed by ((C6), (C7), (C8), (C9)) and ((C4), (C5), (C6), (C9)) form a dihedral angle of 70.3(3)°. The plane of (C1)-(C2)-(C3) forms dihedral angles to the aforementioned planes of 85.9(4) and 89.5(4)°, respectively. The molecules are linked via C-H···O/F interactions. 相似文献
895.
896.
A Three‐Step Method for the Deposition of Large Cuboids of Organic–Inorganic Perovskite and Application in Solar Cells 下载免费PDF全文
Saeed Shahbazi Mahdi Malekshahi Byranvand Dr. Fariba Tajabadi Dr. Shahrara Afshar Dr. Nima Taghavinia 《Chemphyschem》2016,17(15):2389-2394
A three‐step method for the deposition of CH3NH3PbI3 perovskite films with a high crystalline structure and large cuboid overlayer morphology is reported. The method includes PbI2 deposition, which is followed by dipping into a solution of C4H9NH3I (BAI) and (BA)2PbI4 perovskite formation. In the final step, the poorly thermodynamically stable (BA)2PbI4 phase converts into the more stable CH3NH3PbI3 perovskite by dipping into a solution of CH3NH3I. The final product is characterized by XRD, SEM, UV/Vis, and photoluminescence analysis methods. The experimental results indicate that the prepared perovskite has cuboids with high crystallinity and large sizes (up to 1 μm), as confirmed by XRD and SEM data. Photovoltaic investigations show that the three‐step method results in higher solar cell efficiency (15 % enhancement in efficiency) with a better reproducibility than the conventional two‐step deposition method. 相似文献
897.
Daohong Liao Shaoqiang Yang Jianyu Wang Jian Zhang Benke Hong Fan Wu Prof. Dr. Xiaoguang Lei 《Angewandte Chemie (International ed. in English)》2016,55(13):4291-4295
The increase and spread of Gram‐negative bacteria that resistant are to almost all currently available β‐lactam antibiotics is a major global health problem. The primary cause for drug resistance is the acquisition of metallo‐β‐lactamases such as metallo‐β‐lactamase‐1 (NDM‐1). The fungal natural product aspergillomarasmine A (AMA), a fungal natural product, is an inhibitor of NDM‐1 and has shown promising in vivo therapeutic potential in a mouse model infected with NDM‐1‐expressing Gram‐negative bacteria. The first total synthesis and stereochemical configuration reassignment of aspergillomarasmine A is reported. The synthesis highlights a flexible route and an effective strategy to achieve the required oxidation state at a late stage. This modular route is amenable to the efficient preparation of analogues for the development of metallo‐β‐lactamase inhibitors to potentiate β‐lactam antibiotics. 相似文献
898.
Jae‐Sung Bae Eunkyung Jeon Su‐Young Moon Wangsuk Oh Sun‐Young Han Jeong Hun Lee Prof. Sung Yun Yang Prof. Dong‐Myung Kim Prof. Ji‐Woong Park 《Angewandte Chemie (International ed. in English)》2016,55(38):11495-11498
The preparation of bicontinuous nanoporous covalent frameworks, which are promising for caging active enzymes, is demonstrated. The frameworks have three‐ dimensionally continuous, hydrophilic pores with widths varying between 5 and 30 nm. Enzymes were infiltrated into the bicontinuous pore by applying a pressured enzyme solution. The new materials and methods allowed the amount of caged proteins to be controlled precisely. The resulting enzyme‐loaded framework films could be recycled many times with nearly no loss of catalytic activity. Entropic trapping of proteins by a bicontinuous pore with the right size distribution is an unprecedented strategy toward facile in vitro utilization of biocatalysts. 相似文献
899.
900.
近年来,多米诺反应作为一种合成复杂分子的高效手段已得到有机合成化学家的广泛关注。该反应过程中,不需改变反应条件和添加试剂,中间体也无需分离和提纯,实现了原子经济和环境友好。通过C-H键活化直接构建碳-碳键和碳-杂原子键,大大拓展了传统偶联反应的底物范围,同样具有高原子经济性,已经广泛地作为多米诺反应中的一个高效步骤。此外,钯催化剂运用广泛,能够与多种官能团兼容,是多米诺反应的理想金属催化剂。本文综述了基于钯催化C-H键活化的多米诺反应的最新研究进展,以反应中钯的价态变化进行分类,介绍有关反应的特点、优势及其在天然产物合成中的应用。 相似文献