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181.
The hydrothermal reaction of 1,2-dicyanobenzene with NaN3 in the presence of Cd(NO3)2 affords a novel 2D cadmium tetrazolyl-benzoate,{Cd(tzbz)(H2O)}n (H2tzbz is 2-(5-tetrazolyl)-benzoate). The tzbz ligand is generated in situ through the 2+3 Sharpless cycloaddition reaction and hydrolyzation. Its crystal structure was determined by single-crystal X-ray diffraction method. The crystal crystallizes in the orthorhombic system,space group Pbca with a=9.6659(19),b=7.6366(15),c=25.964(5) ,V=1916.5(7) 3,Z=8,Mr=318.57,Dc= 2.208 g/cm3,F(000)=1232 and μ=2.276 mm-1. The Cd(Ⅱ) atom is coordinated by four tzbz ligands and one water molecule to form a severely distorted pentangle bipyramid. While each tzbz ligand connects to four Cd(Ⅱ) atoms in a μ4-η1,η2,η1,η1,η1 coordination mode to construct a 2D architecture of the title complex. Additionally,the title complex exhibits strong fluorescence at room temperature in the solid state.  相似文献   
182.
Novel thermally crosslinkable fluorine‐containing poly(arylene ether ketone)s comprised of 2,3,5, 6‐tetrafluoro‐1,4‐phenylene moiety were synthesized by the termination of polymer chain ends with propargyl ether groups in order to improve solvent resistance. Crosslinking reaction occurred over 250°C through the formation of both chromen ring and polyene structure. This structure change brought about not only the outstanding solvent resistance but also the increase in glass transition temperature (Tg). The cured films also exhibited excellent thermal stability, transparency and hydrophobicity derived from fluorine atoms. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
183.
Summary N-Acylanthranilamides react with dibromotriphenylphosphorane in the presence of triethylamine as HBr captor to give 4-imino-4H-3,1-benzoxazines in good yields. If the reaction is carried out without acid acceptor, N-acetylanthranilamides yield 2-methyl-4-quinazolones, whereas N-benzoylanthranilamides give 2-phenyl-4-imino-4H-3,1-benzoxazines. It has also been found that 2-methyl-4-imino-4H-3,1-benzoxazines rearrange under the influence of HCl or HBr into the respective 2-methyl-4-quinazolones; 2-phenyl-4-imino-4H-3,1-benzoxazines, however, do not undergo such a rearrangement.
Synthese und Umlagerung von 4-Imino-4H-3,1-benzoxazinen
Zusammenfassung Die Umsetzung von N-Acyl-anthranilsäure-amiden mit Triphenyldibromphosphoran in Gegenwart von Triethylamin als HBr-Akzeptor führt mit guten Ausbeuten zu 4-Imino-4H-3,1-benzoxazinen. Wird die Reaktion ohne säurebindendes Mittel durchgeführt, dann entstehen aus N-Acetyl-anthranilsäure-amiden 2-Methylchinazolone-4, jedoch erhält man aus N-Benzoylanthranilsäure-amiden 2-Phenyl-4-imino-4H-3,1-benzoxazine. 2-Methyl-4-imino-4H-3,1-benzoxazine erleiden unter dem Einfluß von HBr oder HCl eine Umlagerung in entsprechende 2-Methylchinazolone-4, während 2-Phenyl-4-imino-4H-3,1-benzoxazine zu einer solchen Umlagerung nicht befähigt sind.
  相似文献   
184.
Bis-citrato 1a-d , bis-citramalato 2 and bis-malato 3 germanate(IV) complexes were synthesized from germanium dioxide and citric acid, citramalic acid and malic acid respectively and were identified with IR, NMR and elementary analysis. Crystal 1a is triclinic, space group P1 with a = 7.919(2), b = 7.968(3), c = 9.605(3) Å, α = 94.25(3), β = 108.03(2), γ= 113.05(3)°, Z = 1, and the final residue, R(F), is 0.033 for 2583 reflections. Crystal 2 is monoclinic, space group C2 with a = 10.226(4), b = 12.802(4), c = 6.141(1) Å, β = 100.75(2)°, Z = 2, and the final residue, R(F), is 0.034 for 934 reflections. Both 1a and 2 have slightly distorted octahedral structures with citrate or citramalate ions as a tridentate ligand that forms five-, six- and seven-membered rings with the central metal. There is a two-fold axis through the central atom of compound 2 instead of the inversion center of 1a . Same structures for these six complexes are indicated because the spectral patterns of the other four compounds, 1b-d and 3 , are similar to those of compounds 1a and 2 .  相似文献   
185.
设计合成了具有降血糖活性的3-甲基-1-苯基-4-[4-[[5-甲基-2-(4-取代芳基)-噁唑-4-基]甲氧基]-芳亚甲(苄)基]}-2-吡唑啉-5-酮类化合物.用丁二酮单肟和(取代的)苯甲醛环合、氯化得到氯甲基噁唑衍生物,与对羟基苯甲醛或香兰醛缩合,再与3-甲基-1-苯基-2-吡唑啉-5-酮进行Knoevenagel反应及催化氢化得到目标化合物(Ⅰ和Ⅱ),共合成了16个未见文献报道的新化合物,并利用元素分析、IR、MS和1HNMR确证了化合物的结构.初步药理试验结果表明,所合成的化合物有抑制血糖升高的倾向以及能明显加强和延长外源性胰岛素的降血糖作用,其中化合物Ⅰb,Ⅰd和Ⅰf尤为突出,说明这类化合物可能有增强胰岛素敏感性的作用.  相似文献   
186.
冠醚液晶出现至今仅十几年,由于其具有冠醚和液晶的各种性质而受到人们的关注[‘-‘1.我们在已有工作的基础上,设计合成了5种酸胺型冠醚液晶分子(4—8),其中3种分子(4-6)具有液晶性.合成路线如下:1结果与讨论合成样品4-8经IR、MS、‘HNMR和元素分析确证其结构.用DSC和Texture图测定了4-6的液晶性质,其结果见图1.化合物7、8无液晶性,分子长径比分别为5.8:I,满足一般律状向列液晶分子长径比的要求.当在其分子链中增加1个苯环(5、6)时,分子的刚性链比例增大,整个分子的刚性增加,则具有液晶性.双臂型冠醚液…  相似文献   
187.
报道了 1 (偶氮苯基 ) 3 ( 3,5 二溴 2 吡啶 ) 三氮烯的合成及其与镉的显色反应。在TritonX 1 0 0存在下 ,于pH 1 0 .9的Na2 B4O7 NaOH缓冲介质中 ,镉与ABDBPDT形成摩尔比 1∶3型红色配合物。试剂及配合物的最大吸收波长分别为 430nm和 5 30nm。表观摩尔吸光系数为 1 .75× 1 0 5L·mol- 1 ·cm- 1 。镉含量在 0 μg/2 5mL~ 1 2 μg/2 5mL范围内符合比耳定律  相似文献   
188.
[Mg(HF)2](SbF6)2 and [Ca(HF)2](SbF6)2 monocrystals were grown from the corresponding hexafluoroantimonates(V) dissolved in anhydrous hydrogen fluoride. [Mg(HF)2](SbF6)2 crystallizes in the space group Pnma (no. 62) with a=1249.1(4) pm, b=1230.2(4) pm, c=699.1(2) pm, V=1.0742(6) nm3, Z=4. Magnesium is octahedrally coordinated by six fluorine atoms from which two belong to two HF molecules. The structure can be represented by alternating rows of magnesium and antimony atoms running parallel to the c-axis. Magnesium atoms are connected by cis bridging Sb(2)F6 units along the a-axis and by trans bridging Sb(1)F6 units along the b-axis. In this way a three-dimensional network is formed.[Ca(HF)2](SbF6)2 crystallizes in the space group P21/n (no. 14) with a=935.2(3) pm, b=1088.7(3) pm, c=1104.8(3) pm, β=106.697(5)°, V=1.0774(5) nm3, Z=4. The coordination sphere around the calcium atom consists of eight fluorine atoms which define the vertices of an Archimedean antiprism. The two HF molecules directly coordinate the calcium atom and their fluorine atoms are placed in the corners of different square faces of the Archimedean antiprism. The Ca-F(HF) distances are shorter than the Ca-F(Sb) distances. The Sb(1)F6 and Sb(2)F6 groups have four equatorial bridging fluorine atoms, while the Sb(3)F6 groups have only two bridging trans F ligands. The Ca atoms in the [−1,0,1] plane are connected by equatorial F ligands of Sb(1)F6 and Sb(2)F6 units, forming a [Ca(SbF6)+]n layer. These layers are connected by trans bridging Sb(3)F6 groups. HF molecules occupy the space between these layers and additionally contribute to the connection between the layers by hydrogen bonding.  相似文献   
189.
A series of new platinum(II) and platinum(IV) complexes of the type [PtII(HMI)2X] (where HMI=hexamethyleneimine, X=dichloro, sulfato, 1,1-cyclobutanedicarboxylato [CBDCA], oxalato, methylmalonato, or tatronato) and [PtIV(HMI)2Y2Cl2] (where Y=hydroxo, acetato, or chloro) were synthesized and characterized by infrared (IR) spectroscopy, 13C and 195Pt nuclear magnetic resonance (NMR) spectroscopy and elemental analysis. Among the complexes synthesized, [PtII(hexamethyleneimine)2(1,1-cyclobutanedicarboxylato)]·H2O was examined by single-crystal X-ray diffraction. The slightly distorted square planar coordination environment of the platinum metal includes the amino group of the hexamethyleneimine (HMI) molecule and the oxygen atoms of the carboxylato ligand. The cyclobutanedicarboxylic acid (CBDCA) molecule adopts six-member chelating rings with platinum. Hydrogen bonding plays an important part in holding the crystal lattice together.  相似文献   
190.
Functionalized Alkyne Complexes of Tungsten(VI). Syntheses and Crystal Structures of [WCl4(Et? Se? C?C? Se? Et)(THF)] and [WCl4(Et? Te? C?C? Te? Et)(THF)] The title compounds have been prepared by reactions of [WCl4(SEt2)2] with the alkynes Et? X? C?C? X? Et (X = Se, Te) in CCl4 solution and subsequent addition of tetrahydrofurane. Both complexes were characterized by crystal structure determinations. [WCl4(Et? Se? C?C? Se? Et)(THF)]: Space group P21/n, Z = 4, structure determination with 2942 unique reflections, R = 0.038. Lattice dimensions at 20°C: a = 934.2, b = 1639.5, c = 1189.5 pm, β = 96.497°. [WCl4(Et? Te? C?C? Te? Et)(THF)]: Space group P21/n, Z = 4, structure determination with 4097 unique reflections, R = 0.067, Lattice dimensions at ?70°C: a = 899.2, b = 1691.9, c = 1213.3 pm, β = 96.82°. The complexes have monomeric molecular structures with the oxygen atom of the THF molecules in trans-position to the side-on bound alkyne ligands.  相似文献   
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