Two—dimensional Network Crown Ether Complex.Synthesis and Crystal Structure of 18—Crown—6 Complex：[K（18—C—6）]2[Cd—（nmt）2]

The novel complex [K(18-C-6)]2[Cd(mnt)2][18-C-6-18-crown-6,nmt=1,2-dicyanoethene-1,2-dithiolate,C2S2-(CN)2^2-] was synthesized and characterized by elemental analysis,IR spectrum and X-ray diffraction analysis.The complex displays two-dimensional network structure of [K(18-C-6)] complex segments and [Cd(nmt)2] complex segment bridged by S-K-S,S-K-N and N-K-N interactions between adjacent[K(18-C-6)] and [Cd(mnt)2]units.     

Construction of Crown Ether‐Stoppering [3]Rotaxanes Based on N‐Hetero Crown Ether Host

Crown ether usually plays the role of macrocyclic host in supramolecular chemistry, but here the crown ether is also utilized as the stoppers in rotaxanes. In this work, we designed and synthesized two [3]rotaxanes containing four crown ether components by using an approach of template‐directed clipping reaction, of which, two crown ether components were employed as the macrocyclic hosts to assemble the mechanically interlocked framework while another two crown ether units located on the two ends of ammonium template acting as the stoppering groups of rotaxanes. Their self‐assembling process was monitored by the ¹H NMR and one of the single crystal structures of [3]rotaxane was obtained.     

一种新型四氮杂取代三环冠醚的晶体结构及其配合物的合成与表征

合成了一种新型的四氮杂取代的三环结构冠醚4,13-二氧-1,7,10,16-四氮杂三环[14.2.1.1^7,10]二十烷(L7), 低温条件下在乙醚中培养出其单晶, 用X射线衍射法测定了晶体结构. 该晶体属单斜晶系, 空间群P2₁/n, 晶胞参数a＝0.8984(7) nm, b＝1.0805(9) nm, c＝1.1040(9) nm; Z＝2, β＝111.707(13)°; V＝0.9958(14) nm³, D_c＝1.189 g/cm³, μ＝0.092 mm^－1, F(000)＝392, R₁＝0.0649, wR₂＝0.1714. 制备了配体L7与金属盐的配合物, 分析结果表明, 配体L7与金属离子形成1∶1型的配合物.     

Squalyl Crown Ether Self‐Assembled Conjugates: An Example of Highly Selective Artificial K+ Channels

The natural KcsA K⁺ channel, one of the best‐characterized biological pore structures, conducts K⁺ cations at high rates while excluding Na⁺ cations. The KcsA K⁺ channel is of primordial inspiration for the design of artificial channels. Important progress in improving conduction activity and K⁺/Na⁺ selectivity has been achieved with artificial ion‐channel systems. However, simple artificial systems exhibiting K⁺/Na⁺ selectivity and mimicking the biofunctions of the KcsA K⁺ channel are unknown. Herein, an artificial ion channel formed by H‐bonded stacks of squalyl crown ethers, in which K⁺ conduction is highly preferred to Na⁺ conduction, is reported. The K⁺‐channel behavior is interpreted as arising from discreet stacks of dimers resulting in the formation of oligomeric channels, in which transport of cations occurs through macrocycles mixed with dimeric carriers undergoing dynamic exchange within the bilayer membrane. The present highly K⁺‐selective macrocyclic channel can be regarded as a biomimetic alternative to the KcsA channel.     

端烯基液晶冠醚推动钠离子在微液/液界面的转移

用循环伏安法研究新型载体端烯基液晶冠醚推动钠离子的转移,结果表明,钠离子的转移由扩散控制.探讨了影响钠离子转移的因素,如端烯基液晶冠醚和钠离子的浓度等.求算出端烯基液晶冠醚在1,2-二氯乙烷中的扩散系数为(2.61±0.12)×10^-6cm²/s,端烯基液晶冠醚和钠离子在1,2-二氯乙烷中所形成的配合物稳定常数lgβ_o=5.7.     

Octyl 1‐(5‐tert‐butyl‐1H‐pyrazol‐3‐yl)‐2‐(4‐chlorophenyl)‐1H‐benzimidazole‐5‐carboxylate: complex sheets built from N—H...N,C—H...N and C—H...O hydrogen bonds

In the title compound, C₂₉H₃₅ClN₄O₂, the bond lengths provide evidence for aromatic delocalization in the pyrazole ring but bond fixation in the fused imidazole ring, and the octyl chain is folded, rather than adopting an all‐trans chain‐extended conformation. A combination of N—H...N, C—H...N and C—H...O hydrogen bonds links the molecules into sheets, in which the hydrogen bonds occupy the central layer with the tert‐butyl and octyl groups arranged on either side, such that the closest contacts between adjacent sheets involve only the octyl groups. Comparisons are made with the supramolecular assembly in some simpler analogues.     

Direct Synthesis of Poly(potassium 3‐sulfopropyl methacrylate) Cylindrical Polymer Brushes via ATRP Using a Supramolecular Complex With Crown Ether

A supramolecular complex between an ionic monomer 3‐sulfopropyl methacrylate (SPMAK) and crown ether 18‐crown‐6 (18C6) has been employed to prepare a strong anionic cylindrical polyelectrolyte brush poly(potassium 3‐sulfopropyl methacrylate) (PSPMAK) by atom transfer radical polymerization (ATRP) in polar solvent dimethyl sulfoxide (DMSO). This strategy solved the problem of the solubilities of the incompatible hydrophobic poly‐initiator and hydrophilic ionic monomer. The formation of the PSPMAK brush is well proven by ¹H NMR, aqueous gel permeation chromatography (GPC), dynamic light scattering (DLS), static light scattering (SLS), atomic force microscopy (AFM), and cryogenic transmission electron microscopy (cryo‐TEM) measurements. Cleavage of the side chains and further analysis reveal that the initiating efficiency of the polymerization is as low as 0.35.

     

取代芳香族冠醚配合物的合成、晶体结构及其与DNA相互作用的研究

合成了冠醚3,3’-二甲基二苯并-18-冠-6（MDB₁₈-C-6）,并以该化合物为配体分别与镍（Ⅱ）、钯（Ⅱ）和K₂（i-mnt）作用,进一步合成了配合物[K（MDB18-C-6）（CH₃COCH₃）]₂[Ni（i-mnt）₂]（1）及配合物[K（MDB18-C-6）（CH₃SOCH₃）]₂[Pd（i-mnt）₂]（2）。通过元素分析、红外光谱、紫外光谱、核磁共振氢谱、质谱等测试手段对其结构进行表征,用X-射线单晶衍射测定了配合物1和配合物2的晶体结构。利用紫外吸收光谱、荧光光谱和圆二色光谱等光谱分析法研究了配合物与小牛胸腺DNA（CT-DNA）的作用,结果表明两种配合物与DNA都具有相互作用,配合物主要是通过影响DNA的螺旋结构,从而引起DNA的构象变化,并且配合物2的作用性能大于配合物1。     

取代芳香族冠醚配合物的合成、晶体结构及其与DNA相互作用的研究

合成了冠醚3,3′-二甲基二苯并-18-冠-6(MDB18-C-6),并以该化合物为配体分别与镍(Ⅱ)、钯(Ⅱ)和K2(i-mnt)作用,进一步合成了配合物[K(MDB18-C-6)(CH3COCH3)]2[Ni(i-mnt)2](1)及配合物[K(MDB18-C-6)(CH3SOCH3)]2[Pd(i-mnt)2](2)。通过元素分析、红外光谱、紫外光谱、核磁共振氢谱、质谱等测试手段对其结构进行表征,用X-射线单晶衍射测定了配合物1和配合物2的晶体结构。利用紫外吸收光谱、荧光光谱和圆二色光谱等光谱分析法研究了配合物与小牛胸腺DNA(CT-DNA)的作用,结果表明两种配合物与DNA都具有相互作用,配合物主要是通过影响DNA的螺旋结构,从而引起DNA的构象变化,并且配合物2的作用性能大于配合物1。     

Designing and Constructing a High‐Temperature Molecular Ferroelectric by Anion and Cation Replacement in a Simple Crown Ether Clathrate

Molecular ferroelectrics have displayed a promising future since they are light‐weight, flexible, environmentally friendly and easily synthesized, compared to traditional inorganic ferroelectrics. However, how to precisely design a molecular ferroelectric from a non‐ferroelectric phase transition molecular system is still a great challenge. Here we designed and constructed a molecular ferroelectric by double regulation of the anion and cation in a simple crown ether clathrate, 4 , [K(18‐crown‐6)]⁺[PF₆]^?. By replacing K⁺ and PF₆^? with H₃O⁺ and [FeCl₄]^? respectively, we obtained a new molecular ferroelectric [H₃O(18‐crown‐6)]⁺[FeCl₄]^?, 1 . Compound 1 undergoes a para‐ferroelectric phase transition near 350 K with symmetry change from P21/n to the Pmc21 space group. X‐ray single‐crystal diffraction analysis suggests that the phase transition was mainly triggered by the displacement motion of H₃O⁺ and [FeCl₄]^? ions and twist motion of 18‐crown‐6 molecule. Strikingly, compound 1 shows high a Curie temperature (350 K), ultra‐strong second harmonic generation signals (nearly 8 times of KDP), remarkable dielectric switching effect and large spontaneous polarization. We believe that this research will pave the way to design and build high‐quality molecular ferroelectrics as well as their application in smart materials.     

Bis{2‐[(phenylimino)ethyl]‐1H‐pyrrol‐1‐ido‐κ2N,N′}nickel(II): a supramolecular structure formed by C—H...π hydrogen bonds

In the title compound, [Ni(C₁₂H₁₁N₂)₂], the Ni^II cation lies on an inversion centre and has a square‐planar coordination geometry. This transition metal complex is composed of two deprotonated N,N′‐bidentate 2‐[(phenylimino)ethyl]‐1H‐pyrrol‐1‐ide ligands around a central Ni^II cation, with the pyrrolide rings and imine groups lying trans to each other. The Ni—N bond lengths range from 1.894 (3) to 1.939 (2) Å and the bite angle is 83.13 (11)°. The Ni—N(pyrrolide) bond is substantially shorter than the Ni—N(imino) bond. The planes of the phenyl rings make a dihedral angle of 78.79 (9)° with respect to the central NiN₄ plane. The molecules are linked into simple chains by an intermolecular C—H...π interaction involving a phenyl β‐C atom as donor. Intramolecular C—H...π interactions are also present.     

A Displacive‐Type Metal Crown Ether Ferroelectric Compound: Ca(NO3)2(15‐crown‐5)

Following the Curie symmetry principle and Aizu rule, we discovered there is a centrosymmetric‐to‐noncentrosymmetric phase transition in Ca(NO₃)₂(15‐crown‐5) at T_c=205 K. The transition was confirmed by differential scanning calorimetry and second harmonic generation measurements. The transition gives rise to excellent ferroelectricity, such as a giant dielectric anomaly, with faster polarization switching (5×10^?5 s) of up to 10⁷ times without showing fatigue. The ferroelectric mechanism is attributable to the coordination environmental distortion of the central Ca atom. This finding can throw light on the further research in metal–organic ferroelectrics.     

Synthesis and Cation Recognition Study of Novel Benzo Crown Ether Functionalized Enamine Derivatives

A novel series of benzo crown ether (dibenzo 18-crown-6 ether, benzo 18-crown-6 ether, and benzo 15-crown-5 ether) functionalized enamines derivatives from amino benzo crown ether (4-amino dibenzo 18-crown-6 ether, 4-amino benzo 18-crown-6 ether, 4-amino benzo 15-crown-5 ether) and substituted 3-(dimethylamino)-1-phenylprop-2-en-1-one compounds have been synthesized. All the synthesized compounds were characterized by infrared, ¹H NMR, ¹³C NMR, distortionless enhancement polarization transfer, and mass and elemental analysis techniques. The cation recognition property for benzo crown ether enamine 8a was studied by absorption and fluorescence spectroscopy.     

新型席夫碱型液晶冠醚的合成与性质

新型席夫碱型液晶冠醚的合成与性质;席夫碱; 冠醚; 热致性液晶; 合成     

Synthesis,structural analysis,spectral investigations,and DFT calculations of 1‐(3‐amino‐4‐thia‐1,2‐diazaspiro[4.11]hexadec‐2‐en‐1‐yl)ethan‐1‐one

1‐(3‐amino‐4‐thia‐1,2‐diazaspiro[4.11]hexadec‐2‐en‐1‐yl)ethan‐1‐one was synthesized and experimentally characterized by using FT‐IR, ¹H NMR, ¹³C NMR, and UV–Vis spectroscopy. The structure of the compound was confirmed by single‐crystal X‐ray diffraction. In the crystal structure, the molecules are linked by pairs of N‐H⋯N hydrogen bonds, forming centrosymmetric dimers with the graph‐set motif. The water molecule also plays an important role in the stabilization of the crystal structure, bridging the dimers to form a two‐dimensional supramolecular network. The molecular geometry, frontier molecular orbitals, vibrational frequencies, electronic properties, and molecular electrostatic potential were calculated using density functional theory (DFT) with the B3LYP/6‐311G(d,p) basis set. Geometric parameters, vibrational assignments, and electronic properties such as calculated energies, excitation energies, and oscillator strengths were compared with the experimental data, and it was seen that the theoretical results support the experimental parameters.     

Conversion of 3‐amino‐4‐arylamino‐1H‐isochromen‐1‐ones to 1‐arylisochromeno[3,4‐d][1,2,3]triazol‐5(1H)‐ones: synthesis,spectroscopic characterization and the structures of four products and one ring‐opened derivative

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.     

Supramolecular Assembly of Gold Nanoparticles Mediated by Polypseudorotaxane with Thiolated β‐Cyclodextrin

Summary: A water‐soluble gold nanoparticle aggregate 2 was prepared by chloroauric acid and a polypseudorotaxane 1 of mono‐6‐thio‐β‐cyclodextrin with poly(propylene glycol) bis(2‐aminopropyl ether) ( ≈ 2 000) in the presence of sodium borohydride in N,N‐dimethylformamide (DMF) solution. The investigative results indicated that the gold nanoparticle aggregate 2 might act as an efficient DNA‐cleavage reagent.

A typical TEM image of gold nanoparticle aggregate 2 .     

Synthesis of 1‐Methyl‐3‐aryl‐substituted Titanocene and Zirconocene Dichlorides and Crystal Structure of Bis[η5‐1‐methyl‐3‐(α, α‐dimethylbenzyl) cyclopentadienyl] titanium Dichloride

The syntheses of a series of l‐methyl‐3‐aryl‐substituted titanocene and zirconocene dichlorides are reported. These complexes are synthesized by the reaction of 2‐ and 3‐methyl‐6, 6‐dimethylfulvenes (1:4) with aryllithium, followed by the reaction with TiCl₄·2THF, ZrCl₄ and (CpTiCl₂)₂O respectively, to give complexes 1–5. The complex [η⁵‐1‐methyl‐3‐(α, α‐dimethylbenzyl) cyclopentadienyl] titanium dichloride has been studied by X‐ray diffraction. The red crystal of this complex is monoclinic, space group P2_t/C with unit cell parameters: a =6.973(6) × 10^?1 nm, b =36.91(2) × 10^?1 nm, c = 10.063(4) × 10^?1 nm, α=β= γ = 93.35(5)°, V = 2584(5) × 10^?3 nm³ and Z = 4. Refinement for 1004 observed reflections gives the final R of 0.088. There are four independent molecules per unit cell.     

[Na(DB18-C-6)(H2O)2][Na(DB18-C-6)(SCN)2]：Two-Di-mensional Network Complex Assembled by π-π Stacking Interactios,Hydrogen Bonds and Electrostatic Interactions

A novel two‐dimensional network dibenzo‐18‐crown‐6 (DB18‐C6) complex: [Na (DB18‐C‐6) (H₂O)₂] [Na (DB18‐C‐6) (SCN)₂] has been isolated and characterized by elemental, IR and X‐ray diffraction analysis. The crystal structure belongs to monoclinic, space group P2₁/c with cell dimensions a = 1.06178(7), b = 1.40243(8), c = 3.03496(19) nm, β = 90.4220(10)°, V = 4.5292(5) nm³, Z=4, D_calcd =1.351 g/ cm³, F(000) = 1936, R₁ = 0.0369, wR₂ = 0.0821. The most interesting feature in this structure is that complex cation and complex anion form a two‐dimensional network via τ‐τ stacking interactions, hydrogen bonds and electrostatic interactions.     

电导法对几种液晶冠醚与KClO_4络合作用的研究

近年来国内外相继报道了在冠醚核心上引入取代基合成出一系列具有液晶特性的冠醚化合物,它们除具有普通液晶的电光、电磁及超声等特性外,还具有选择性络合金属离子的能力。研究这类化合物结构及性能将有助于选择和制备对金属离子具有高度识别能力的输送膜。为此,我们研究了以二苯并-18-冠-6(DB-18-C-6)及苯并-15-冠-5(B-15-C-5)为核心衍生的胆甾型冠醚化合物。经红外、核磁、质谱及元素分析确定其结构,由差热分析和偏光显微镜观察证明其具有液晶特性,并用电导法探讨了该系列液晶化合物与KClO_4在25℃时的络合特性,测定了络合比及络合常数。