水热合成超分子网络化合物[Mn(phen)_2I_2] (phen=邻菲咯啉)及晶体结构

采用水热法设计并合成了一个新颖的超分子网络化合物[Mn(phen)_2I_2],并对其进行了元素分析,红外光谱分析和X-射线单晶衍射分析.结果表明:该化合物属三斜晶系, P_1~-空间群,晶胞参数为:a=0.92705(19) nm,b=1.0370(2) nm,c=1.2775(3) nm,α=77.32(3) °,β=81.26 (3) °,γ=70.30(3) °,V=1.1240(4) nm~3,Z= 2.该化合物通过四种C-H...I氢键相互作用与两种π-π堆积相互作用把各个独立的结构单元连接成了超分子网络化合物.     

Synthesis and Crystal Structure of a New Copper(Ⅱ) Complex with 4-Cyanobenzoic Acid

A new Cu(Ⅱ) complex [Cu(4-cba)(l,10-phen)(H2O)2](NO3) (4-Hcba = 4-cyanobenzoic acid) has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100℃ and structurally characterized by single-crystal X-ray diffraction. Crystallographic data: C20H16CuN4O7, Mr= 487.91, triclinic, space group P1, a = 7.8420(2), b = 9.1070(2), c = 15.1140(6) A,α=76.889(9), β = 81.332( 11 ), γ = 74.844(11 )°, V = 1009.89(5) A3, Z = 2, Dc = 1.605 g/cm3, F(000)=498,μ=1.134 mm-1,the final R = 0.0379 and wR = 0.0865 for 2977 observed reflections with I ＞ 2σ(Ⅰ).The Cu(Ⅱ) atom is coordinated by two terminal water molecules, one chelating 1,10-phen molecule and one monodentate 4-cba ligand to form a slightly distorted square pyramid. The title complex molecules are connected through hydrogen bonds and π-π stacking interactions to generate a 2D layered network. The thermogravimetric analysis of the title complex has also been discussed.     

Synthesis and Crystal Structure of catena-Poly[bis-(benzimidazole)cobalt(Ⅱ) μ- Phthalato]

The title polymeric complex [Co(C8H4O4)(C7H6N2)2]n has been prepared and its crystal structure was determined by X-ray diffraction method. The crystal belongs to monoclinic,space group C2/c with a = 7.7865(12), b = 20.4215(18), c = 13.4880(14) (A),β = 103.298(2)°, V = 2087.3(4) (A)3, Mr = 459.32, Z = 4, Dc= 1.462 g/cm3,μ = 0.859 mm-1, F(000) = 940, R = 0.0636 and wR = 0.1639 for 1278 observed reflections (I ＞ 2σ(Ⅰ)). The complex assumes a distorted tetrahedral coordination geometry, formed by two phthalate anions and two benzimidazoles (bzim). The phthalate anions bridge the neighboring Co(Ⅱ) atoms to form the polymeric chains. The centroid distance of 3.471(3) (A) between the parallel bzim rings of adjacent polymeric chains suggests the existence of π-π stacking.     

基于背景光调制的复合光傅里叶变换轮廓术

提出一种基于背景光调制的用于傅里叶变换轮廓术测量范围的复合光栅,该光栅通过调制一正弦条纹和不含任何相位信息的背景光来抑制零频,较基于相移技术的复合光栅有更大的优势:背景光只含直流分量,使得复合光栅的频谱更加简单,有利于滤出载波信息,提高测量精度;对从复合光栅中解调出来的背景光只涉及平均值校准,校准过程更为简单;解调出的背景光与物体表面的反射率成正比,具有潜在的应用价值。采用Matlab程序对该复合光栅进行了数值模拟,并对该光栅实用性进行了实验研究,结果证实了该光栅用于抑制零频、扩大傅里叶变换轮廓术测量范围的有效性,且提高了测量精度。     

A phosphonated copillar[5]arene: Synthesis and application in the construction of pH-responsive supramolecular polymer in water

A phosphonated-functionalized copillar[5]arene was designed and synthesized. ¹H NMR, ¹³C NMR, ESI-MS and HR-MS were performed to provide converging evidences of the structure of obtained copillar[5]arene. Driven by hydrophobic interactions and C–H···π interactions between the decyl moiety and the pillar[5]arene cavity, a pH-responsive linear supramolecular polymer was fabricated from this phosphonate-functionalized AB type monomer in water. Concentration-dependent ¹H NMR, NOESY, DOSY, and specific viscometry were carried out to study the supramolecular polymerization process.     

NMR-Spectroscopic, computational and mass-spectrometric investigations on the cis/trans analogues of 2,3,4-trihydronaphthalene-1-one

NMR-Spectroscopic, computational and mass-spectrometric studies of the cis/trans isomers of N-[8-(acetylamino)-4-(2,2-dimethyl-1,1-diphenyl-silapropoxy)-6-fluoro-5-methyl-1-one-2,3,4-trihydronaphthyl]acetamide (1a and 1b), obtained as intermediates in the synthesis of an important class of alkaloid molecules, are reported. ¹H and ¹³C NMR analyses show an unusual axial preference of the TBDPSi- (tert-butyldiphenylsilyl) group in position 4 in both the isomers. Mass spectrometric evidence demonstrates that trans isomer has a higher affinity for ammonium ions than the cis isomer and that only the ammonium adduct [1b+NH₄]⁺ and the protonated molecule [1b+H]⁺ show the fragmentation in which loss of benzene is observed. Moreover, molecular mechanics and semi-empirical calculations indicate that a group of trans conformers tend to place one of the phenyl rings of the TBDPSiO- group in a offset π-stacked geometry with the compound's aromatic ring. The combination and the detailed analyses of these experimental and theoretical results could support the π-π interaction obtained as a conformational preference in the trans isomer.     

Improving the gelation properties of 3,5-diaminobenzoate-based organogelators in aromatic solvents with additional aromatic-containing pendants

A family of 3,5-diaminobenzoate derivatives containing different Cbz-protected α- or β-amino side pendant chains and different aromatic-containing ester functionalities was prepared. It was found that the additional aromatic rings in the Cbz- and aromatic-containing ester moieties significantly improved the gelation properties of the resulting organogelators in aromatic solvents. Infrared and circular dichroism spectroscopy revealed that both H-bonding and π-π aromatic stacking interactions were the main driving forces for gelation.     

Azo and azoxythiacrown ethers: synthesis and properties

A series of 16- and 18-membered azo- and azoxythiacrown ethers have been synthesized by reductive macrocyclization of the respective bis(nitrophenoxy)oxaalkanes. The aromatic residues located in the polyether region of the molecule were introduced to macrocyclic skeletons and their affinities toward different groups of metal cations in ion-selective electrodes were described. X-ray structures for one dinitropodand and one azoxybenzothiacrown exhibiting strong π–π and π–H interactions have been found.     

Polymorphism in a benzo[b][1,4]diazepine derivative: Crystal structure,phase behavior and selective influence of solvents

Ethyl 4-[(Z)-3-ethoxy-2,3-dioxopropylidene]-4,5-dihydro-1H-benzo[b][1,4]diazepine-2-carboxylate forms two polymorphic modifications α and β, which differ in molecular conformations, as well as in the dimension of H-bonded supramolecular motifs in crystals that are a 1D chain or a 0D dimer, respectively. The formation of polymorphs can be controlled by choice of the solvent used. Crystallization from a solution in a polar protic solvent, ethanol, results in the thermodynamically favorable α-form, while using a low-polarity solvent, chloroform, and melt crystallization lead to the metastable β-form.     

Highly selective adenine recognition by a macrocyclic host molecule employing multiple hydrogen bonding and π-π stacking interactions

A new macrocyclic host, which contains a 2,6-bis(oxazol-2-yl)pyridine unit and a 2,7-dialkoxynaphthalene unit tethered by the appropriate length of alkyl side chains is prepared. This host undergoes highly selective complex formation with an adenine nucleobase, accompanied by a fluorescence response in CHCl₃ by a combination of multiple hydrogen bonding and π-π stacking interactions.