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1.
Two new coordination polymers based on 1,1′-(1,4-butanediyl)bis(imidazole) (bbi) and 5-hydroxyisophthalic acid (OH-BDC), [Co2(HO-BDC)2(bbi)2]·H2O (1) and [Zn(HO-BDC)(bbi)] (2), have been hydrothermally synthesized. The complexes were characterized by single-crystal X-ray diffraction, IR, and elemental analysis. The structure determination reveals that 1 manifests a deeply corrugated 2-D layer with a (4,4) lattice. For 2, there is a highly undulating 2-D (4,4) layer structure. The layers penetrate by each other to give a 2-D → 3-D parallel interpenetrating network. Fluorescence properties and thermal stabilities of 1 and 2 in the solid state have been studied.  相似文献   

2.
Two new Wells–Dawson based compounds containing alkali metals, [Ag(H2biim)2]2·[Ag5(H2biim)10Na2(H2O)2(H3/2P2W18O62)2]·12H2O (1) and [Cd(H2biim)2?K(P2W18O62)1/2] (2) (H2biim?=?2,2′-biimidazole), have been synthesized under hydrothermal conditions. In 1, two-supporting Wells–Dawson anions are linked by a [Ag(H2biim)2]+ subunit to form a dimer. The adjacent dimers are further connected by Na+ through (POM)O-Na-O(POM) bonds to build a 1-D chain. In 2, adjacent anions are linked by two [Cd2(H2biim)2]4+ subunits and a 1-D chain is formed. Furthermore, the anion in the chain is fused by six K+ ions and a 3-D framework is obtained. The alkali metals exhibit crucial influence on the conversion of dimensionality assisting anions and Ag-H2biim subunits to construct 1-D and 3-D frameworks. The electrochemical and photocatalytic properties of 1 and 2 have been investigated.  相似文献   

3.
A new tetranuclear complex, {[Cu(phen)(OH)]4(H2O)2}?·?(SO4)2?·?8H2O (1) (phen = 1,10-phenanthroline), has been synthesized and characterized by elemental analysis, UV-Vis, IR, TG, and single-crystal X-ray diffraction. Complex 1 exhibits a 3-D supramolecular network with a 1-D metal–water chain consisting of tetranuclear hydroxo-bridged copper(II) clusters and water octamers and a 2-D water–sulfate layer containing cyclic water octamers with five types of O–H?···?O hydrogen-bonding motifs. The free ligand and its complex were screened for antibacterial activity against Gram-positive and Gram-negative bacteria.  相似文献   

4.
本文讨论了I群-D2群V系数,给出在I群单值表示下的计算值。将以I群为出发点的群分解链延伸到其D2子群。还列出了D2群V系数的计算结果。  相似文献   

5.
TheSynthesesof1┐Dimensional(1┐D)Chain,2┐DLayered,and3┐DMicroporousAlumino┐phosphateswithOccludedAmineorAmmoniumTemplatesfromA...  相似文献   

6.
肖陆飞  陈晨  吴杰颖  田玉鹏  金葆康 《化学学报》2011,69(21):2543-2549
通过固态Wittig反应合成一种新型D-π-D'-π-D型二茂铁衍生物:4-二丁氧基-2,5-二(2-二茂铁基乙烯基)苯[(Fc-CH=CH)2BZ(RO)2].利用核磁共振氢谱(1H NMR),红外光谱(FT-IR)和质谱(EI-MS)等对化合物进行了表征,通过单晶X-ray衍射确定了它的晶体结构为单斜晶系,C2/c...  相似文献   

7.
Two mononuclear metal-organic complexes, [Co(Hmpdc)2(H2O)4]·4H2O 1 and [Ni(Hfmpdc)2(H2O)4]·6H2O 2, were prepared from 2,6-dimethylpyridine-3,5-dicarboxylic acid (Hzmpdc) and 4-furyl-2,6-dimethylpyridine-3,5-dicarboxylic acid (H2fmpdc) with M(NO3)2 salts, respectively, and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectroscopy, and photoluminescent measurement. Complex 1 crystallizes in triclinic, space group P1 with a = 7.634(5), b = 8.695(5), c = 10.757(6)A, α = 69.647(7), β = 69.957(8), γ = 83.733(7)°, V = 628.9(7)A^3, Dc = 1. 561 g/cm^3,μ(MoKa) = 0.763 mm^-1, F(000) = 309, Z = 1, the final R = 0.0553 and wR = 0.1469 for 1909 observed reflections (Ⅰ 〉 2σ(Ⅰ)). Complex 2 crystallizes in monoclinic, space group P21/n with a = 9.5934(16), b = 12.422(2), c = 14.826(3) A, β = 105.201(2)°, V = 1705.0(5)A3, Dc = 1. 479 g/cm^3,μ(MoKa) = 0.655 mm^-1, F(000) = 796, Z = 2, the final R= 0.0351 and wR = 0.0889 for 2387 obsevved reflections (Ⅰ 〉 2σ(Ⅰ)). In the crystal structures of 1 and 2, diverse supramolecular motifs from 1-D chains/ladders to 3-D networks are constructed from corresponding distinct [M^Ⅱ(H2O)8] ion clusters as the second building units, respectively. The solid state compounds of 1 and 2 show similar photoluminescent spectra with emission maximum at ca.  相似文献   

8.
Abstract

Pseudo-β-D (D-2) and L-fructopyranose (L-2), 1(S) and (1R)-(1,2/-3,4)-4-C-hydroxymethyl-1,2,3,4-cyclohexanetetrol, have been synthesized, starting from optically active endo-adducts of furan and acrylic acid, following the modified procedure used for the preparation of the racemic modification. It has been demonstrated that the D and L-enantiomers are nearly as sweet as D-fructose, and the former is somewhat sweeter than the latter.  相似文献   

9.
A coordination polymer, [Co(2-mpac)2(4,4′-bpy)·(4,4′-bpy)] n (2-mpac: 5-methyl-2-pyrazinecarboxylic acid; 4,4′-bpy: 4,4′-bipyridine), has been synthesized through hydrothermal synthesis and structurally characterized by X-ray single crystal diffraction. Single crystal X-ray diffraction analysis reveals a 3-D network featuring a 1-D tunnel filled with 4,4′-bpy molecules. Elemental analysis, IR, thermogravimetric analysis, and magnetic properties are presented.  相似文献   

10.
11.
丁基氟脲嘧啶的β-D葡萄吡喃糖苷的合成   总被引:1,自引:0,他引:1  
孙昌俊 《有机化学》1987,7(6):449-451
目前,人们大多采用 Koenigs—Knorr法,E.Fischer 法,原酸酯法和(?)唑啉等方法合成糖苷类化合物。本文通过相转移催化,以十二烷基苄基二甲基溴化铵为催化剂,使2,3,  相似文献   

12.
Reaction of trans(N)-[Co(D-pen)2]? (pen = penicillaminate) or trans(N)-[Co(L-pen)2]? with [MCl2(L)] {M = Pd or Pt, L = 2,2′-bipyridine (bpy) or 1,10-phenanthroline (phen)} in the presence of tetrafluoroborate stereoselectively gave an optically active S-bridged dinuclear complex, [M(L){Co(D-pen)2}]BF4 · 2H2O or [M(L){Co(L-pen)2}]BF4 · 2H2O. The mixture of equimolar amounts of these enantiomers in H2O crystallizes as [M(L){Co(D-pen)2}]0.5[M(L){Co(L-pen)2}]0.5BF4 · 4H2O (DLbpyM · 4H2O, DLphenM-A · 4H2O), in which the enantiomeric complex cations are included by the ratio of 1 : 1. In crystals of DLbpyM · 4H2O and DLphenM-A · 4H2O, [M(L){Co(D-pen)2}]+ and [M(L){Co(L-pen)2}]+ interact stereospecifically with each other through π-conjugated systems to form dimeric structures. Other racemic crystals with the same chemical compositions as DLphenM-A · 4H2O, DLphenM-B · 4H2O, were obtained from equimolar amounts of [M(phen){Co(D-pen)2}]+ and [M(phen){Co(L-pen)2}]+ in aqueous acetonitrile solution. In the crystals of DLphenM-B · 4H2O, [M(phen){Co(D-pen)2}]+ and [M(phen){Co(L-pen)2}]+ are arranged alternately while overlapping phen planes, and the π electronic systems of phen interact with each other. Although stereospecific hydrogen bonds between the coordinated ?NH2 and ?COO? groups are formed in both DLphenM-A · 4H2O and DLphenM-B · 4H2O, their bonding modes differ noticeably from each other. As a result, DLphenM-A · 4H2O builds up 1-D ladder-like networks due to the stereospecific π–π stackings and hydrogen bondings between enantiomers, while 2-D sheet-like networks are established for DLphenM-B · 4H2O.  相似文献   

13.
Three novel organic-inorganic hybrid borotungstates {[Ni(phen)2(H2O)]2H(α-BW12O40)}·4H2O (1), [CuI(2,2'-bipy)(4,4′-bipy)0.5]2{[CuI(2,2′-bipy)]2CuI(4,4′-bipy)2(α-BW12O40)} (2) and {[CuI(4,4′-bipy)]3H2(α-BW12O40)}·3.5H2O (3) (phen=1,10-phenanthroline, 2,2′-bipy=2,2′-bipyridine, 4,4′-bipy=4,4′-bipyridine) have been hydrothermally synthesized and structurally characterized by elemental analyses, IR, UV spectra, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), single-crystal X-ray diffraction, X-ray photoelectron spectroscopy (XPS) and photoluminescence. The structural analysis reveals that 1 consists of a 0-D bisupporting polyoxometalate cluster where two [Ni(phen)2(H2O)]2+ cations are grafted on the polyoxoanion [α-BW12O40]5- through two terminal oxygen atoms, 2 shows a 1-D infinite chain constructed from [α-BW12O40]5- polyoxoanions and {[CuI(2,2′-bipy)]2CuI(4,4′-bipy)2}3+ cations by means of alternating fashion, and 3 displays an unprecedented 2D extended structure built by [α-BW12O40]5- polyoxoanions and -CuI-4,4′-bipy- linear chains, in which each [α-BW12O40]5- polyoxoanion acts as a tetradentate inorganic ligand and provides three terminal oxygen atom and one two-bridging oxygen atom. The presence of NiII and WVI in 1, CuI ions and WVI in 2 and 3 are identified by XPS spectra. The photoluminescence of 2 and 3 are also investigated.  相似文献   

14.
氨基酸是构成多肽的基本单位,肽链中不同的氨基酸及氨基酸所含基团的不同使其在化学和生物活性等方面有着不同的性质。通过改变肽链中不同氨基酸来修饰肽链的结构和环境,能赋子肽链新的功能。天然氨基酸由于结构的原因,无法满足特殊的需要。随着生物化学合成、分离和测试技术的  相似文献   

15.
建立在线GPC-GC/MS技术测定苹果中2,4-D残留的快速检测方法。采用正己烷振荡提取试样中2,4-D,正丁醇-H2SO4溶液衍生化,通过在线GPC-GC/MS系统自动完成从GPC净化、浓缩到GC/MS分析。该方法中2,4-D在实际样品检测中的平均加标回收率为87.9%~99.9%,相对标准偏差(RSD)为2.7%~8.1%。方法的检测限为0.005 mg/kg。  相似文献   

16.
以乙酰氨基丙二酸酯和苄卤为原料,经缩合、碱性水解、脱羧和脱乙酰基,合成了一组卤代-D,L-苯丙氨酸盐酸盐,利片j核磁共振谱(1H NMR)和质谱(MS)表征了产物的结构,利用元素分析确定了其组成.  相似文献   

17.
李玉玲  王圣田 《色谱》1986,4(4):257-257
辛硫磷农药残留的测定,国外报道用OV-101涂布于Gas-Chrom Q及用OV-225或OV-275涂布于Chromasorb W(HP)作色谱柱填料等气相色谱法,国内尚未见气相色谱法测定该农药残留的报道。我们在测定青菜中辛硫磷农药残留时,使  相似文献   

18.
19.
An open-framework zincophosphate, [C4N3H16][Zn4.5(PO4)4] 1, has been hydro- thermally synthesized and characterized by single-crystal X-ray diffraction. It crystallizes in the tetragonal space group P4 with a = 14.512(5), c = 8.914(3)A, V = 1877.3(11)A3, C4H16NaO16P4Zn4.50, Mr = 780 24: Z = 4, Dc = 2.761 g/cm^3,μ= 6.103 mm^-1, F(000) = 1536, T = 298(2) K, R = 0.0416 and wR = 0.0816. In the structure, ZnO4 and PO4 tetrahedra are linked to each other, forming four-membered rings which are connected variably to form two secondary building units (SBUs). The SBUs are connected so as to generate two chains along the c axis, which are further linked together alternatively via common oxygen atoms (Zn-O-P) giving rise to 8-ring-channels in the [001] direction, and the protonated guest diethylenetriamine (DETA) molecules sit in the middle of these channels. Other characterizations are also described by elemental analysis, thermal analysis and IR and fluorescent spectra.  相似文献   

20.
The complex [Cu2(H2dhbd)2(tpy)2]·CH3OH·4H2O 1 (H4dhbd =2,3-dihydroxybutanedioic acid, tpy = 2,2':6',2''-terpyridine) has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis. The crystal is of triclinic, space groups Pi with a= 8.6859(17), b = 11.223(2), c = 12.275(2)A, α = 112.454(3), β= 98.435(3), γ = 105.593(3)°, V= 1022.5(3) A^3, Z = 1, C38H42Cu2N6O18, Mr = 997.86, Dc = 1.621 g/cm^3, μ= 1.127 mm^-1, F(000) = 514, T = 293(2) K, the final R = 0.0539 and wR = 0.1394 for 3550 observed reflections with I 〉 2σ(I). In the dinuclear unit, two Cun atoms are bridged by two H2dhbd chelate anions, forming a 14-membered ring, in which the distance of Cu…Cu atoms is 7.0526(12)A. Adjacent dinuclear units are constituted through π-π interactions and C-H…O hydrogen-bonding interactions, fashioning the final 3-D supramolecular framework with 1-D open channels. Variable-temperature magnetic susceptibility measurement indicates the presence of weak antiferromagnetic exchange interactions between Cu^II ions.  相似文献   

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