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A new vicinal dioxime ligand with two crown-ether groups, 1,2-bis[(monoaza[15]crown-5)-N-Yl]-glyoxime(LH2), has been prepared from cyanogen di-N-oxide and monoaza[15]crown-5. Ni(II), Pd(II), and Pt(IV) complexes of LH2 with or without alkali-metal ions bound to macrocyclic groups have been isolated. The high affinity of [Pd(LH)2] and [Ni(LH)2] for the K+ ion is observed in solvent extraction experiments. A single-crystal X-ray structure confirms the postulated geometry of [Pd(LH)2]- The Pd-atom of the centro-symmetric molecule has square-planar PdN4 coordination where Pd–N distances range from 1.978(3) to 1.970(3) Å. The N–Pd–N intraligand angle is 79.9(1)°.  相似文献   

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 The (1:1) Na+ equilibrium constants, Ke1, of macrocyclic ethers of [12]crown-4, [12]crown-5 and [18]crown-6 were determined with a Na+ ISE in the presence of a second cation e.g. Li+, K+ and Ca2+ in dioxane/water (50/50). We estimated the (1:1) equilibrium constants, K e2 of the macrocyclic ethers with Li+, K+ and Ca2+ by this way. The binding selectivity of a macrocyclic ether between two cations was estimated in the same binary solvent mixture where the water hydration role is diminished. Results showed clearly the effect of macrocyclic size and cation radii in a solution. Received October 27, 1998. Revision March 22, 1999.  相似文献   

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The fullerene-crown ether conjugates (±)- 1 to (±)- 3 with trans-1 ((±)- 1 ), trans-2 ((±)- 2 ), and trans-3 ((±)- 3 ) addition patterns on the C-sphere were prepared by Bingel macrocyclization. The trans-1 derivative (±)- 1 was obtained in 30% yield, together with a small amount of (±)- 2 by cyclization of the dibenzo[18]crown-6(DB18C6)-tethered bis-malonate 4 with C60 (Scheme 1). When the crown-ether tether was further rigidified by K+-ion complexation, the yield and selectivity were greatly enhanced, and (±)- 1 was obtained as the only regioisomer in 50% yield. The macrocyclization, starting from a mixture of tethered bis-malonates with anti ( 4 ) and syn ( 10 ) bisfunctionalized DB18C6 moieties, afforded the trans-1 ((±)- 1 , 15%), trans-2 ((±)- 2 , 1.5%), and trans-3 ((±)- 3 , 20%) isomers (Scheme 2). Variable-temperature 1H-NMR (VT-NMR) studies showed that the DB18C6 moiety in C2-symmetrical (±)- 1 cannot rotate around the two arms fixing it to the C-sphere, even at 393 K. The planar chirality of (±)- 1 was confirmed in 1H-NMR experiments using the potassium salts of (S)-1,1′-binaphthalene-2,2′-diyl phosphate ((+)-(S)- 19 ) or (+)-(1S)-camphor-10-sulfonic acid ((+)- 20 ) as chiral shift reagents (Fig. 1). The DB18C6 tether in (±)- 1 is a true covalent template: it is readily removed by hydrolysis or transesterification, which opens up new perspectives for molecular scaffolding using trans-1 fullerene derivatives. Characterization of the products 11 (Scheme 3) and 18 (Scheme 4) obtained by tether removal unambiguously confirmed the trans-1 addition pattern and the out-out geometry of (±)- 1 . VT-NMR Studies established that (±)- 2 is a C2-symmetrical out-out trans-2 and (±)- 3 a C1-symmetrical in-out trans-3 isomer. Upon changing from (±)- 1 to (±)- 3 , the distance between the DB18C6 moiety and the fullerene surface increases and, correspondingly, rotation of the ionophore becomes increasingly facile. The ionophoric properties of (±)- 1 were investigated with an ion-selective electrode membrane (Fig. 2 and Table 2), and K+ was found to form the most stable complex among the alkali-metal ions. The complex between (±)- 1 and KPF6 was characterized by X-ray crystal-structure analysis (Figs. 3 and 4), which confirmed the close tangential orientation of the ionophore atop the fullerene surface. Addition of KPF6 to a solution of (±)- 1 resulted in a large anodic shift (90 mV) of the first fullerene-centered reduction process, which is attributed to the electrostatic effect of the K+ ion bound in close proximity to the C-sphere (Fig. 5). Smaller anodic shifts were measured for the KPF6 complexes of (±)- 2 (50 mV) and (±)- 3 (40 mV), in which the distance between ionophore and fullerene surface is increased (Table 3). The effects of different alkali- and alkaline-earth-metal ion salts on the redox properties of (±)- 1 were investigated (Table 4). These are the first-ever observed effects of cation complexation on the redox properties of the C-sphere in fullerene-crown ether conjugates.  相似文献   

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2-Thioxo-1,2-dihydrobenzo[d][1,3]thiazin-4-one (TDBTO), a new thiazin-one derivative, was synthesized and investigated. The crystal structure of TDBTO (CsHsNOS2, Mr = 193.8) was determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 6.946(3), b = 7.402(3), c = 8.954(4)A, α = 66.931(7)°,β = 89.866(7)°, γ = 72.289(7)°, V = 399.8(3) A^3, Z = 2, Mr = 195.25, Dc = 1.622 g/cm^3,μ = 0.606 mm^-1, F(000) = 200, R = 0.0361 and wR = 0.1032. There exist intermolecular hydrogen bond of N(1)-H(1A)-..O(1) and weak C(6)-H(6A)...O(1) contact in the structure as well as face-to-face π-π stacking interactions between the benzene ring and the thiazin ring of an adjacent benzothiazin unit. The photoinduced proton transfer reaction, transforming the initial thione into thiol form, was found, and the latter form was characterized by UV absorption spectra, fluo-rescence spectra and infrared spectra.  相似文献   

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GU Wen  HAO Yun  CHEN  Hong-Tu WANG  Shi-Fa 《结构化学》2013,(12):1904-1910
The title compound (C29H33NO2, 3) was synthesized and structurally characterized by elemental analysis, IR, MS, 1H- and 13C-NMR and single-crystal X-ray diffraction. The crystal is of monoclinic system, space group P21 with a = 14.428(3), b = 7.3440(15), c = 22.768(5) A, β = 95.17(3)°, V = 2402.7(8) A3, Z = 4, Mr = 427.56, Dc = 1.182 g/cm3, F (000) = 920, 2(MoKa) = 0.71073 A,μ = 0.073 mm-1, the final R= 0.0670 and wR= 0.1002 for 2437 reflections with I〉 2σ(I) Two crystallographically independent molecules with different conformations co-exist in the structure. The crystal structure is stabilized by intermolecular C-H…π interactions which make the molecules stack along the b axis. In addition, the preliminary cytotoxic assay showed that the title compound exhibited moderate inhibitory activity against KB and SW1116 cells.  相似文献   

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A new tridentate benzimidazole derivative, 2,6-bis (benzo[1,2-d:4,5-d′]diimidazole-2′-yl) -pyridine (Bzdiimpy), was prepared from o-phenylenediamine in five steps with improved methods according to the literature in good yield. The crystal structure was determined by X-ray diffraction analysis. It crystallized in monoclinic, space group P21/c, with a=1.170 8(4) nm, b=2.479 6(9) nm, c=1.215 9(4) nm, β=114.641(7)°, Z=1, R=0.035 0, wR2=0.089 0. The bzdiimp molecule displayed an almost planar structure and formed a zig-zag chain through weak interactions between imidazole-N and [SnCl6]2--Cl. Its electronic absorption and emission spectra were measured and compared with the reported analogue 2,6-bis (benz[1,2-d:4,5-d′]imidazole-2′-yl)-pyridine (Bzp). CCDC: 239203.  相似文献   

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The reaction of C60F18 with phenol, 2-naphthol and quinol in the presence of ferric chloride leads to initial electrophilic substitution (aryldefluorination). This occurs at both ortho and para positions for phenol, at the ortho position for quinol, and at the relatively hindered but most reactive 1-position for 2-naphthol. It is followed, where sterically favourable, by HF loss either between the OH group and F (rendered adjacent as a result of a 1,3-shift) or to attack of the OH group at an adjacent double bond with loss of a beta-fluorine, giving benzofurano[2',3':10,26]hexadecafluoro[60]fullerene derivatives. The reaction is accompanied by some complete defluorination leading, in reaction with phenol and with 2-naphthol, to the formation of benzofurano[2',3':1,2][60]fullerene and naphtho[2,1:b]furano[d:1,2][60]-fullerene, respectively. The mechanism of base-catalysed reaction of phenols with C60Cl6 is re-evaluated.  相似文献   

15.
The intramolecular hetero Diels-Alder reaction of the benzy-lidenebarbituric acid derivative 1 to give the ortho and meta products 2 and 3 is studied under high pressure up to 6 kbar in various solvents. The kinetics is measured by on-line FT-IR spectroscopy up to 3 kbar. The cycloaddition shows a pressure-dependent increase in regioselectivity in favour of the ortho adduct 2. The activation volumes, ΔV, are determined to be -(33.1· 1.2) and -(34.2· 1.5) cm3· mol−1 for the reactions in dichloromethane and tetrahydrofuran at 100°C, respectively. For the cycloaddition in toluene and acetonitrile the activation volumes are found to be -(13.4· 1.5) and -(17.0· 4.1) cm3· mol−1, respectively. Contrary to the large solvent effect on the activation volume, only a minor effect on the activation volume differences, ΔΔV, is observed. Measurement of the molar volumes of 1 and the cycloadducts 2 and 3 show a strong solvent dependency.  相似文献   

16.
The title compound(14 S)-2,14-diphenyl-6,6 a,11,12-tetrahydro-5 H,10 H,14 H-[1,8] naphthyridino[1,2-c]pyrido[3,2,1-ij]quinazoline-3-carbonitrile(C_(31) H_(26) N_4, M_r = 454.56) has been synthesized with 2-aminonicotinaldehyde and 3-oxo-3-phenylpropanenitrile as starting materials, and its crystal structure was determined by single-crystal X-ray diffraction for the first time. The crystal belongs to the triclinic system, space group P1 with a = 8.5833(8), b = 11.9168(12), c = 14.4424(14) ?, α = 84.208(3)o, β = 88.427(3)o, γ = 73.704(3)o, V = 1410.7(2) ?~3, Z = 2, F(000) = 480, μ = 0.064 mm~(–1), S = 0.966, the final R = 0.0484 and wR = 0.1388 for 5041 observed reflections with I 2s(I) and 316 variable parameters. The preliminary biological tests show that the title compound has a good antitumor activity against K562 in vitro.  相似文献   

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A new complex, [Cd(succ)PIP]n (PIP=2‐phenyl‐imidazo[4,5‐f]1,10‐phenanthroline, H2‐succ=succinate), was synthesized and characterized by X‐ray crystallography, elemental analysis, and TG‐DTG. The results show that the complex crystallizes in an orthorhombic space group Pcca; a=14.065(2) Å, b=9.901(8) Å, c=28.933(2) Å and Z=8. The structure of the complex is one‐dimensional chain [Cd(succ)PIP]n, and each Cd2+ is five‐coordinated by two chelating nitrogen atoms from one PIP ligand, three oxygen atoms from three different succ dianionic ligands to form a distorted trigonal‐bipyramida geometry. The constant‐volume combustion energy of the complex, ΔcU, was determined by an intelligent micro‐rotating‐bomb calorimeter (IMRBC‐type I) at 298.15 K. Then the standard molar enthalpy of combustion, ΔcHm?, and the standard molar enthalpy of formation, ΔfHm? have been calculated.  相似文献   

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单分子磁体[Mn4(CF3COO)4(hmp)6]的合成、晶体结构及磁学性质   总被引:1,自引:0,他引:1  
以[Mn12O12(CF3COO)16(H2O)4]·2CF3COOH·4H2O和2-羟甲基吡啶(hmpH)为起始物, 在四氢呋喃溶液中合成了一种新的四核锰配合物[Mn4(CF3COO)4(hmp)6]. X射线单晶衍射结果表明, 该配合物属于单斜晶系, P21/c空间群, 晶胞参数a=1.3663(3) nm, b=1.4705(3) nm, c=1.4734(3) nm, β=98.51(3) °, V=2.9276 nm3, Z=2. 配合物中有两个CF3COO-基团与七配位Mn2中心相连, 其中一个为单齿配体, 另一个是双齿配体. 直流磁化率研究结果表明, 该配合物具有较高的自旋基态, 而交流磁化率依赖于外场频率变化极值的出现表明该配合物是一种单分子磁体.  相似文献   

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分子组装在材料科学、催化和生物化学中具有潜在的应用前景,所以分子组装引起了化学、固体物理学和生物学等领域科学家们的普遍关注犤1犦。分子组装常用的方法是使用具有配位能力的金属配合物作为建筑块与过渡金属阳离子反应。氰基桥联多核配合物由于其结构的多样性和具有特别优异的磁性质,近10年来在配位化学领域倍受关注犤2~8犦。在系列配合物犤M(en)2犦犤Ni(CN)4犦(M=Ni,Cu,Zn,Cd等)中,犤Cu(en)2犦犤Ni(CN)4犦和犤Cd(en)2犦犤Ni(CN)4犦的晶体结构已经通过单晶衍射的方法测得犤9,10犦。在犤Cu(en)2犦犤Ni(CN)4犦中,Cu原子为六配…  相似文献   

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A dinuclear cadmium complex [Cd_2(bpbb)_2Cl_2(μ-Cl_2)], where bpbb is 1,2-bis(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene, was synthesized and characterized by X-ray singlecrystal structure analyses. Crystal data: C_(64)H_(44)Cd_2Cl_4N_8, M_r = 1291.67, triclinic system, space group P1, a = 10.076(3), b = 12.730(4), c = 13.176(4) ?, α = 99.087(3), β = 109.859(3), γ = 112.551(3)°, V = 1384.8(7) ?~3, Z = 1, D_c = 1.549 g/cm~3, λ = 0.71073 ?, μ(Mo Kα) = 1.010 mm~(–1), F(000) = 648, S = 1.062, R = 0.0425 and wR = 0.1130 for 9688 observed reflections with I 2s(I). One 1,2-bis(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene coordinates to one cadmium ion. The cadmium is five-coordinated by three chloride ions and two nitrogen atoms from bpbb. Each cadmium ion is bridged by two chloride ions. The decomposition temperature is up to 420 ℃. The complex emits blue luminescence in DMF solution and in solid powder state.  相似文献   

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