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1.
二次配体结构和[CuCl4]2-构型对层间隧道结构的影响研究   总被引:1,自引:0,他引:1  
郭放  夏芳  宋纯亮  郭文生 《化学学报》2009,67(16):1891-1896
设计合成的质子配体, N,N,N’,N’-四(对甲基苄基)乙二胺(SL1)和N,N,N’,N’-四苄基乙二胺(SL2), 是连有大体积取代基团的含N双齿配体, 它可通过二次球形配位, 与第一络合物[CuCl4]2-形成层间隧道框架结构. 环戊醇分子和乙醇分子分别被填入由SL1和SL2构筑的隧道中, 形成包结化合物. 晶体结构分析结果表明, 这样的配体易于与指导基团通过NH+…Cl-氢键作用进行双齿配位并形成1D带和2D层结构; SL1 2D层间的苄基呈平行堆砌, 形成1D亲水性隧道框架, SL2 2D层间的苄基呈交错堆砌, 形成了1D疏水性隧道框架. 实验结果表明, 层间隧道框架结构的孔径及极性与第二配体的分子长度、指导基团的构型以及客体分子的形状大小有关.  相似文献   

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在NaOH存在下,N,N′,N″,N-四乙酸-1,4,7,10-四氮杂环十二烷、N,N′,N″,N-四乙酸-1,4,8,11-四氮杂环十四烷、N,N′,N″,N-四甲磷酸-1,4,7,10-四氮杂环十二烷和N,N′,N″,N-四甲磷酸-1,4,8,11-四氮杂环十四烷分别与LaCl3·7H2O或GdCl3·6H2O通过大环配体络合物直接合成法,得到八个络合物,产率为46.7%~90.7%。  相似文献   

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《Analytical letters》2012,45(13):2433-2439
Abstract

A highly sensitive spectrophotometric determination of benzoylperoxide (BPO) based on the color developing reaction between N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD) and BPO in the presence of cerium(IV) in weakly acidic media is proposed. The calibration graph is linear in the range 0–6000 ng BPO per 10 ml with an apparent molar absorptivity of 4.73 × 105 1 mol?1 cm-1 at 612 nm. The proposed method is about 50-fold more sensitive than N-ethyl-2-naphthylamine (NENA), and application to assays of flour is described.  相似文献   

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A variety of chiral N,N‐bidentate and N,N,N‐tridentate ligands based on the pyridine framework, namely C2‐symmetric dipyridylmethane and terpyridine, N‐(p‐toluensulfinyl)iminopyridines and two kinds of iminopyridines, has been assessed in the asymmetric copper(I)‐catalysed allylic oxidation of cyclic olefins. Catalytic activity and enantioselectivity were found to be highly dependent upon the framework of the ligands, which afforded cycloalkenyl benzoates in low to moderate yields and enantioselectivities. The best yields (up to 70%) and enantioselectivities (up to 53% enantiomeric excess) were obtained with an iminopyridine based on camphane and quinoline skeletons. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

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Three complexes, Na4[DyIII(dtpa)(H2O)]2?·?16H2O, Na[DyIII(edta)(H2O)3]?·?3.25H2O and Na3[DyIII (nta)2(H2O)]?·?5.5H2O, have been synthesized in aqueous solution and characterized by FT–IR, elemental analyses, TG–DTA and single-crystal X-ray diffraction. Na4[DyIII(dtpa)(H2O)]2?·?16H2O crystallizes in the monoclinic system with P21/n space group, a?=?18.158(10)?Å, b?=?14.968(9)?Å, c?=?20.769(12)?Å, β?=?108.552(9)°, V?=?5351(5)?Å3, Z?=?4, M?=?1517.87?g?mol?1, D c?=?1.879?g?cm?3, μ?=?2.914?mm?1, F(000)?=?3032, and its structure is refined to R 1(F)?=?0.0500 for 9384 observed reflections [I?>?2σ(I)]. Na[DyIII(edta)(H2O)3]?·?3.25H2O crystallizes in the orthorhombic system with Fdd2 space group, a?=?19.338(7)?Å, b?=?35.378(13)?Å, c?=?12.137(5)?Å, β?=?90°, V?=?8303(5)?Å3, Z?=?16, M?=?586.31?g?mol?1, D c?=?1.876?g?cm?3, μ?=?3.690?mm?1, F(000)?=?4632, and its structure is refined to R 1(F)?=?0.0307 for 4027 observed reflections [I?>?2σ(I)]. Na3[DyIII(nta)2(H2O)]?·?5.5H2O crystallizes in the orthorhombic system with Pccn space group, a?=?15.964(12)?Å, b?=?19.665(15)?Å, c?=?14.552(11)?Å, β?=?90°, V?=?4568(6)?Å3, Z?=?8, M?=?724.81?g?mol?1, D c?=?2.102?g?cm?3, μ?=?3.422?mm?1, F(000)?=?2848, and its structure is refined to R 1(F)?=?0.0449 for 4033 observed reflections [I?>?2?σ(I)]. The coordination polyhedra are tricapped trigonal prism for Na4[DyIII(dtpa)(H2O)]2?·?16H2O and Na3[DyIII(nta)2(H2O)]?·?5.5H2O, but monocapped square antiprism for Na[DyIII(edta)(H2O)3]?·?3.25H2O. The crystal structures of these three complexes are completely different from one another. The three-dimensional geometries of three polymers are 3-D layer-shaped structure for Na4[DyIII(dtpa)(H2O)]2?·?16H2O, 1-D zigzag type structure for Na[DyIII(edta)(H2O)3]?·?3.25H2O and a 2-D parallelogram for Na3[DyIII(nta)2(H2O)]?·?5.5H2O. According to thermal analyses, the collapsing temperatures are 356°C for Na4[DyIII(dtpa)(H2O)]2?·?16H2O, 371°C for Na[DyIII(edta)(H2O)3]?·?3.25H2O and 387°C for Na3[DyIII(nta)2(H2O)]?·?5.5H2O, which indicates that their crystal structures are very stable.  相似文献   

6.
Highly regioselective homocoupling of N,N-dialkylanilines can be achieved in water with cerium reagents, in which various N,N,N′,N′-tetraalkylbenzidines are obtained from N,N-dialkylanilines either by direct oxidation by cerium(Ⅳ)reagents or by cerium(Ⅲ) reagents in the presence of hydroperoxide.  相似文献   

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配合物[UO2(Bu2NCOCH2CONBu2)(NO3)2]晶体属单斜晶系,P21/c空间群,a=10.744(2),b=13.229(5),c=20.011(8)β,β=99.21(3)°,V=2808(2)β3,Dc=1.07g·cm-3,Z=4,配合物分子中具有直线结构的铀酰离子由六个氧原子配位,其中四个来自硝酸根,另外两个来自羰基,形成平面六角形,六角形的平面与铀酰离子的直线垂直,两个硝酸根处于相邻位置.  相似文献   

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This paper proposes a solid-phase microextraction (SPME) method for the passive sampling and determination of N,N-dimethylacetamide (DMA) and N,N-dimethylformamide (DMF) in air by capillary GC with flame ionization detection. The optimized conditions for SPME method were grab sampling, polydimethylsiloxane/divinylbenzene fiber, extraction for 90 min at 25 +/- 2 degrees C, desorption for 3 min at 220 degrees C, and relative humidity 45 +/- 2%. Under these conditions, the method presented good linearity (R = 0.996), repeatability (%RSD 2.79 and 9.85 for DMF and DMA, respectively), and detection limit (0.021 and 0.024 mg/m3 for DMF and DMA, respectively).  相似文献   

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Azocarboxamide (azcH) has been combined for the first time with [Ru–Cym] to generate metal complexes with N,N‐ and N,O‐coordination mode, [(Cym)Ru(azc)Cl] and [(Cym)Ru(azcH)Cl]+[PF6]?. Geometric and electronic structures of the complexes are reported along with their in vitro activities against different tumour cell lines and preliminary results on solution chemistry. Compound [(Cym)Ru(azc)Cl] exhibited remarkable cytotoxic properties. It was cell‐type specific and had comparable IC50 values towards both cancer cells and their drug‐resistant subline. A tenfold increase in the sensitivity towards [(Cym)Ru(azc)Cl] was noted for the tumour cells with depleted intracellular glutathione (GSH) level, suggesting the essential role of GSH in cell response to this compound.  相似文献   

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研究新型萃取剂从硝酸盐介质中萃取分离稀土元素对于后处理工艺具有重要意义。本文报道以甲苯为稀释剂,N,N,N′,N′-四丁基丙二酰胺(TBMA)从硝酸盐介质中萃取铈(Ⅲ)、镝(Ⅲ)、铒(Ⅲ)、镨(Ⅲ)、钐(Ⅲ)、铽(Ⅲ)、铥(Ⅲ)、镱(Ⅲ)的机理。考察了硝酸浓度、TBMA浓度、盐析剂浓度以及温度对上述三价镧系离子分配比的影响。得出萃合物的组成主要是三配体配合物M(NO3)3·3TBMA;计算出萃取反应的条件平衡常数、萃取平衡常数。温度效应研究表明萃取反应主要是焓驱动的。对萃取分离系数以及TBMA萃取三价镧系离子的规律进行了初步研究。  相似文献   

16.
Mn(III) complexes with tridentate Schiff bases have been prepared and applied as catalyst precursors in epoxidation of alkenes using iodosobenzene as an oxidant providing high conversions and high selectivities when cyclohexene derivatives were studied.  相似文献   

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