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991.
Lithium aluminium amide [LiAI(NHR)4] 5 obtained by treating the primary amine 4 with LiAlH4 could promote the ring opening of epoxide 2 and led to high regioselective product of racemic bis[2-(6-fluoro-2-chromanyl)-2-hydroxyethyl]amine methanesulfonic acid salt 7.  相似文献   
992.
Synthesis and Characterization of Phosphated Konjac Glucomannan Hydrogels   总被引:11,自引:0,他引:11  
Konjac glucomannan (KGM) was crosslinked with sodium tripolyphosphate (STPP) to synthesize hydrogels. The crosslinking reaction was confirmed by FT-IR. The results of degradation test show that the hydrogels retain the enzymatic degradation character of KGM and can be degraded for 74.45% in 5 days by cellulase E0240.  相似文献   
993.
In the title complex, [Ag2(C7H4NO4)2(C16H16S2)], each AgI atom is trigonally coordinated by one S atom of a 2,11‐dithia­[3.3]paracyclo­phane (dtpcp) ligand, and by one N and one O atom of a 6‐carboxy­pyridine‐2‐carboxylate ligand. Dtpcp acts as a bidentate ligand, bridging two inversion‐related AgI atoms to give a dinuclear silver(I) compound. The dinuclear moieties are inter­connected via O—H·O hydrogen bonds to form a two‐dimensional zigzag sheet. Two such sheets are inter­woven viaπ–π inter­actions between pyridine rings, affording an inter­woven bilayer network.  相似文献   
994.
The crystal structure of Ce(IO3)3 consists of one‐dimensional chains of edge‐sharing CeO9 polyhedra which are crosslinked into two‐dimensional layers through bridging IO3 groups. The layers are held together via long I⋯O contacts, resulting in an extended three‐dimensional network. The I—O bond distances and O—I—O angles are normal, lying in the ranges 1.806 (4)–1.846 (4) Å and 89.9 (2)–100.9 (2)°, respectively. The three crystallographically independent iodate groups all show different coordination modes.  相似文献   
995.
In the title compound, [Ir2(C16H13N2O3)4Cl2]·2CH2Cl2, the two Ir atoms, 3.7075 (6) Å apart, are bridged by two Cl atoms which straddle a twofold axis of rotation through the two Ir atoms. Each Ir centre resides in a distorted octa­hedral environment completed by two chelating 2,5‐bis­(4‐methoxy­phenyl)‐1,3,4‐oxadiazole ligands, with trans‐N—N and cis‐C—C dispositions. In the stacking structure, there are two types of hydrogen bonds, involving the meth­oxy substitutent, an N atom of the oxadiazole ring and the dichloro­methane solvent mol­ecules.  相似文献   
996.
Two coordination polymers, namely [Ni(L1)-(ndc)(H2O)] n (1) and [Cu(L2)0.5(ndc)] n (2) (L1 = 1,3-bis(2-methylbenzimidazol-1-ylmethyl)benzene, L2 = 1,4-bis(2-methylbenzimidazole)butane, H2ndc = 2,6-naphthalenedicarboxylic acid) have been synthesized and characterized by single-crystal and powder X-ray diffraction, IR spectroscopy, thermogravimetric analysis, and elemental analysis. Complex 1 features a 2D 3-connected hcb network with 63 topology, which is further extended into a 3D supramolecular framework by O–H···O hydrogen bonding interactions. Complex 2 possesses a 3D threefold interpenetrating (4,5)-connected xah topological network, and its Schläfli symbol is (42.62.82)(46.64). Both complexes exhibit intense luminescence emissions in the solid state and promising catalytic activities for the degradation of Congo red azo dye in a Fenton-like process.  相似文献   
997.
Three coordination polymers, namely {[Ni(L1)(nip)(H2O)]·2H2O} n (1), [Co(L2)(tbip)] n (2), and {[Co2(L3)2(bptc)]·3H2O} n (3) (L1 = 1,4-bis(5,6-dimethylbenzimidazole)butane, L2 = 1,4-bis(5,6-dimethylbenzimidazole)-2-butylene, L3 = 1,3-bis(5,6-dimethylbenzimidazole)propane, H2nip = 5-nitro-isophthalic acid, H2tbip = 5-tert-butyl-isophthalic acid, H4bptc = biphenyl-3,3′,4,4′-tetracarboxylic acid), have been synthesized under hydrothermal conditions and characterized by physicochemical and spectroscopic methods as well as by single-crystal X-ray diffraction analysis. Complexes 1 and 2 both feature a two-dimensional (4,4) layer with (44 × 62) topology. Complex 3 possesses a uninodal 4-connected 2D htb network. The fluorescence spectra and catalytic properties of the complexes for the degradation of methyl orange by sodium persulfate in a Fenton-like process are reported.  相似文献   
998.
In the title complex, {[Mn(C4O4)(C10H8N2)(H2O)]·H2O}n, each MnII ion has a distorted octa­hedral coordination formed by two N atoms of a 2,2′‐bipyridine ligand, three carboxyl O atoms of three different acetyl­ene­dicarboxyl­ate ligands and one coordinated water mol­ecule. The acetyl­ene­dicarboxyl­ate ligands act in a tridentate mode connecting adjacent MnII ions and constructing a two‐dimensional structure which can be regarded as an unusual plywood‐like stacked network.  相似文献   
999.
The complexation behaviors of anthracenecarboxylic acid and water-soluble cationic pillararenes have been investigated by 1H NMR, UV-vis and ITC methods. The cationic pillar[6]arene was found to stepwise form 1:1 and 1:2 complexes, having a large K1 and a relatively small K2 values. Photocyclodimerization of AC within the pillar[6]arene improved the yield of the head-to-head photodimers. Up to 4.97 HH/HT ratio has been reached by optimizing the reaction conditions.  相似文献   
1000.
钛硅ZSM-5沸石分子筛的微波辐射法合成与表征   总被引:2,自引:0,他引:2  
以工业硅溶胶为硅源,廉价的乙醇作模板剂,用微波辐射的方法 成功地合成了高结晶度的钛硅 Z S M 5 分子 筛。确定合 成条 件为:m ol Et O H ∶ m ol Si = 0. 1~ 0.4,微 波反 应釜 压力 为 1 M Pa, 晶化时 间200m in。利用 X R D, S E M , I R 等方法 对钛硅 Z S M 5 分子 筛的物相和晶貌作 了表征,结果表明 钛已进入分子筛骨架。微波辐射法合成大大地缩短了反应时间,简化了操作,合成的样品粒度 小且均匀。  相似文献   
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