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1.
We have systematically studied redox properties of two series of several dozen heteropoly acids (salts) and their derivatives with vanadium and rare-earth elements with Keggin and Dawson structures, e. g. LnHSiMo_(12), SiMo_(12-n)V_n, M_(1.5)PMo_(12), PMo_(12-n)V_n, PW_(12-n_V_n, Ln(PMo_(11))_2, Sm(XMo_(11))_2 and P_2Mo_(18-n)V_n, etc., and obtained their sequence of oxidation. It was found that there is a linear relationship between the reduction potentials of heteropoly anions and the derivatives of heteropoly anions with rare-earth elements with Keggin structure and nq~2 (n and q are the principal quantum number and charge of the central ion respectively). On the basis of the electrostatic model the regularity of oxidation and reduction was rationalized. 相似文献
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本文合成了1-[5-(α-萘)-2 H-四唑-2-乙酰]-4-苯基氨基硫脲5,以及由5衍生的环化产物3-[5-(α-萘)-2 H-四唑-2-甲撑]-4-苯基-1,2,4-三唑啉-5-硫酮6,2-苯胺基-5-[5-(α-萘)-2 H-四唑-2-甲撑]-1,3,4-噻二唑7及2-苯胺基-5-[5-(α-萘)-2 H-四唑-2-甲撑]-1,3,4-(口恶)二唑8。它们的结构均通过元素分析,红外光谱,核磁共振及质谱鉴定。其药理实验正在进行中。初步实验表明,5及6对小麦生长有较强的促进作用。 相似文献
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Ali M. Kuliyev Fakhraddin M. Mamedov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):179-180
Abstract Aromatic thiols belong to a group of not yet sufficiently explored compounds. The presence of an active hydrogen atom makes it possible to conduct various chemical conversions and to obtain new S-substituted derivatives. 相似文献
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M. R. Mahmoud A. Y. Soliman H. M. Bakeer 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):135-143
Abstract 2-Methyl-6-phenyl chromone la and a variety of its derivatives were synthesized. The reactivity of In and other chromones with aromatic aldehydes, hydrazine hydrate, hydrazine derivatives. Hydroxylamine hydrochloride, different primary amines and Grignard reagents was investigated. The I.R. and H1NMR spectra of the products are discussed. 相似文献
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Jairo Quiroga Dayana Pantoja Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(8):884-887
In the title compound, C31H29N3O2, the reduced pyridine ring adopts a conformation intermediate between the envelope and half‐chair forms. The aryl rings of the benzyl and phenyl substituents are nearly parallel and overlap, indicative of an intramolecular π–π stacking interaction. A combination of two C—H...O hydrogen bonds and one C—H...N hydrogen bond links the molecules into a bilayer having tert‐butyl groups on both faces.<!?tpb=19.5pt> 相似文献
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Gerd-Volker Röschenthaler Irene B. Kulik Vadim A. Soloshonok 《Journal of fluorine chemistry》2011,132(10):834-542
Addition of both alkyl phosphites and phosphonate α-carbanions to N-substituted aldimines derived from fluoroalkyl aldehydes presents a convenient method for synthesis of fluoroalkyl α- and β-aminophosphonates in good yield (55-86%) under mild conditions. 相似文献
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The ligand 4,4′-bipyridyl-N,N′-dioxide (4,4′-dpdo) was used in the synthesis of two complexes, {Co(4,4′-dpdo)2[N(CN)2]2(H2O)2} (1) and {Mn(4,4′-dpdo)2[N(CN)2]2(H2O)2} (2). The complexes were found to be isostructural, triclinic, space group P-1 with Z = 1 and the following unit cell parameters: a = 8.158(8) Å, b = 8.865(8) Å, c = 9.477(9) Å; α = 70.988(13)°, β = 78.778(13)°, γ = 71.964(10)°; V = 612.8(10) Å3 for 1; a = 8.247(14) Å, b = 9.001(16) Å, c = 9.707(17) Å; α = 71.02(2)°, β = 78.63(2)°, γ = 72.62(2)°; V = 646(2) Å3 for 2. Final R-values were 0.075 and 0.083 for 1 and 2, respectively. In the molecules of the complexes, Co(II) or Mn(II) cation is coordinated by two O-atoms of two 4,4′-dpdo ligands, two terminal N-atoms of two dicyanamides, and two O-atoms of water molecules. The crystals are molecular, with adjacent complex molecules linked through a system of O-H...N and O-H...O hydrogen bonds. 相似文献
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合成了六种含有乙二醇、多甘醇及多甘醇单醚功能基的树脂。树脂的功能基转化率达93.4—97.5%。树脂2—6对Au(Ⅲ)的吸附率达90—100%,对Pt(Ⅳ)为40—50%,但对共存的Pd(Ⅱ)、Cu~(2+)、Ni(2+)、Cd(2+)等离子甚少吸附。六种树脂的吸金容量在226.3—93.8mg Au(Ⅲ)/g树脂之间。被吸附的金可用3%。硫脲-1N盐酸容液洗脱。洗脱率达95.8%以上。 相似文献
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In this paper, we report a novel two-step synthetic method of the symmetrical and asymmetrical diphosphine ligands 1, 2-bis(ditertbutylphosphino)ethane and 1, 2-bis(phenyltertbutylphosphino) ethane, and simultaneously establish a novel synthetic method of diphosphine ligand 1, 4-bis(phosphinocyclopentyl)butane with larger chelate ring. The former was prepared from the reaction of 1, 2-bis(dichlorophosphino)ethane with Grignard reagent andalkyl lithium, respectively, the latter from the reaction of 1, 4-di-Grignard reagent with PCl_3. Furthermore, a series of organometallic complexes of Pt, Ni containing diphosphine chelate ligand were prepared from the reaction of (COD) PtCl_2 complex with diphosphine. These complexes are very stable. Among these complexes, the molecular structures of (d(t-Bu)pe)-PtCl_2, (dPCypb)PtCl_2 and ((n-Bu) (PCyp))_2PtCl_2 complexes have been determined by X-ray diffraction method indicating they are novel complexes. The influence of diphosphine ligand on the molecular structure 相似文献
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Viktor Vrbel Július Sivý Peter af tefan Marchalín 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(8):817-822
Molecules of (S)‐6‐oxo‐1‐(thiophen‐2‐ylmethyl)piperidine‐2‐carboxylic acid, C11H13NO3S, crystallize as single enantiomers in the space group P21 and the thiophene ring is disordered over two positions, while (S)‐6‐oxo‐1‐(thiophen‐3‐ylmethyl)piperidine‐2‐carboxylic acid, C11H13NO3S, crystallizes as a single enantiomer in the space group P212121. Their absolute configurations were confirmed by anomalous dispersion effects in diffraction measurements on the crystals. The molecules of each compound are linked by a combination of strong O—H...O hydrogen bonds and weak C—H...O interactions, resulting in two‐ and three‐dimensional networks, respectively, in the crystal structures. 相似文献
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The structure of thep-t-butyldihomooxacalix[4]arene triethylamine (1 : 2 complex has been determined by X-ray crystallography. Crystals are monoclinic, space groupCc,a = 22.821(3),b = 15.257(3),c = 16.365(2) Å, = 97.44(1)°,V = 5650(1) Å3,Z = 4,D
calc = 1.03 g cm–3. One triethylamine (Et3N) molecule has one of its ethyl groups pointing inside the cavity of a calixarene molecule; its nitrogen atom is directed exo to this calixarene molecule and is involved in a hydrogen bond with one of the hydroxy groups of a neighbouring calixarene molecule. This scheme leads to columns of alternating host and guest molecules. The other Et3N molecule is in the interhost space. This feature allows us to define the title compound as a complex/clathrate hybrid.Supplementary data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82144 (8 pages). 相似文献
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Rim Benali‐Cherif Radhwane Takouachet El‐Eulmi Bendeif Nourredine Benali‐Cherif 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(7):689-692
Two polymorphs of L‐aspartic acid hydrochloride, C4H8NO4+·Cl−, were obtained from the same aqueous solution. Their crystal structures have been determined from single‐crystal data collected at 100 K. The crystal structures revealed three‐ and two‐dimensional hydrogen‐bonding networks for the triclinic and orthorhombic polymorphs, respectively. The cations and anions are connected to one another via N—H...Cl and O—H...Cl interactions and form alternating cation–anion layer‐like structures. The two polymorphs share common structural features; however, the conformations of the L‐aspartate cations and the crystal packings are different. Furthermore, the molecular packing of the orthorhombic polymorph contains more interesting interactions which seems to be a favourable factor for more efficient charge transfer within the crystal. 相似文献
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侧链聚硅氧烷液晶高分子的合成与表征及应用研究 总被引:4,自引:0,他引:4
液晶高分子既具有独特的液晶性 ,又具有高分子的良好材料性能 ,引起了人们的广泛注意[1~ 9] .侧链液晶高分子大多可以作为功能材料 ,对它们的研究有很大的理论与现实意义 .以往报道的此类化合物的介晶基元大多是通过烷氧基与间隔基相连[10 ] .我们以催化活性很高的铂络和物为催化剂 ,通过硅氢加成反应制备了间隔基与介晶基元通过酰氧基相连的两种侧链聚硅氧烷液晶高分子 ,并对它们的性质进行了初步表征 .发现它们具有很好的液晶性 .已有研究表明侧链聚硅氧烷液晶在气相色谱分离结构近似的物质方面 ,具有易涂渍、选择性及热稳定性优于低分子… 相似文献
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以N 叔丁氧羰酰 L 色氨酸和N 叔丁氧羰酰 L 酪氨酸为印迹分子 ,分别采用光引发聚合和热引发聚合制备了分子印迹聚合物 ,并对聚合物的手性识别能力进行了色谱评价 .结果表明 ,制备的分子印迹聚合物对印迹分子具有特异性的吸附作用 ,光引发聚合的N 叔丁氧羰酰 L 色氨酸的印迹聚合物对印迹分子的选择性因子达到 2 .318,热引发聚合的N 叔丁氧羰酰 L 酪氨酸对印迹分子的选择性因子为 1 373 进一步研究了分子印迹聚合物的孔结构 ,发现光引发聚合的分子印迹聚合物与空白聚合物的孔结构差别比热引发聚合的分子印迹聚合物与空白聚合物的差别更为明显 .对印迹分子洗脱前后的印迹聚合物的孔结构研究进一步表明 ,印迹分子存在于不同类型的孔中 . 相似文献
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尖晶石型铁酸盐的制备和表征研究 总被引:7,自引:0,他引:7
本文采用空气氧化湿法制备尖晶石铁酸盐,得到最佳生成条件为:R-2OH^-/(M^2++F2+)≥1.0;M^2+/Fe^2+=0.5摩尔比;氧化温度343-358K;氧化时间10-25小时。通过XRD、TPR和TPD等方法对其进行表征,讨论了尖晶石型铁酸盐的氧化-还原活及其化学组成和结构的变化。 相似文献
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Daniel E. Vicentes Andrea L. Romero Ricuarte Rodríguez Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(5):446-453
An efficient synthesis of 1‐arylisochromeno[3,4‐d][1,2,3]triazol‐5(1H)‐ones, involving the diazotization of 3‐amino‐4‐arylamino‐1H‐isochromen‐1‐ones in weakly acidic solution, has been developed and the spectroscopic characterization and crystal structures of four examples are reported. The molecules of 1‐phenylisochromeno[3,4‐d][1,2,3]triazol‐5(1H)‐one, C15H9N3O2, (I), are linked into sheets by a combination of C—H…N and C—H…O hydrogen bonds, while the structures of 1‐(2‐methylphenyl)isochromeno[3,4‐d][1,2,3]triazol‐5(1H)‐one, C16H11N3O2, (II), and 1‐(3‐chlorophenyl)isochromeno[3,4‐d][1,2,3]triazol‐5(1H)‐one, C15H8ClN3O2, (III), each contain just one hydrogen bond which links the molecules into simple chains, which are further linked into sheets by π‐stacking interactions in (II) but not in (III). In the structure of 1‐(4‐chlorophenyl)isochromeno[3,4‐d][1,2,3]triazol‐5(1H)‐one, (IV), isomeric with (III), a combination of C—H…O and C—H…π(arene) hydrogen bonds links the molecules into sheets. When compound (II) was exposed to a strong acid in methanol, quantitative conversion occurred to give the ring‐opened transesterification product methyl 2‐[4‐hydroxy‐1‐(2‐methylphenyl)‐1H‐1,2,3‐triazol‐5‐yl]benzoate, C17H15N3O3, (V), where the molecules are linked by paired O—H…O hydrogen bonds to form centrosymmetric dimers. 相似文献