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IntroductionThe interactions between molecules involvingaromatic ring systems are of interest because oftheir effects on the structures and aggregation ofimportant biomolecules,on template efficiency in avariety of organic reactions,and on the solid statestructures of a variety oforganic molecules[1] .Con-sistent are the analysis results of more than 2 0 0phenylalanine- phenylalanine interactions in thecrystal structures of various proteins,which leadsto the following conclusions.( 1 ) Direct …  相似文献   

3.
Stereoselective Michael addition and Michael-aldol tandem reaction of diorganyl diselenides and disulfides with conjugated alkynones mediated by samarium diiodide were studied. The reaction temperature was critical for the stereoselectivity, β-Organylselenoalkenones or β-organylthioalkenones and γ-organylselenoallylic alcohols or γ-organylthioallylic alcohols were prepared in good yields.  相似文献   

4.
With recent interest in polymer-based nanocomposites, nano-alumina has receivedconsiderable attention because of their high hardness, high strength and good wearresistance. Improvements in mechanical, tribological, conductive and barrier propertiesof some…  相似文献   

5.
The reaction of [Fe2S2(CO)6] with one equiv.of o-OCH3C6H4CH2Br under the re-duction of LiBHEt3 in dry THF afforded a tetranuclear cluster [(μ4-S){(μ-SCH2(o-OCH3)Ph)Fe2(CO)6}2](1).Complex 1 crystallizes in monoclinic,space group P21/n with a = 16.5623(6),b = 12.8265(5),c = 18.2702(7) ,β = 115.95(1)o,V = 3489.9(4) 3,Z = 4,μ = 1.87 mm-1,Dc = 1.709 Mg/m3,T = 296(2) K,C28H18Fe4O14S3,Mr = 898.03,F(000) = 1800,S = 1.10,R = 0.032 and wR = 0.058.Complex 1 consists of two diiron fragments possessing a {Fe2(CO)6} core.The two diiron units are bridged by an inorganic sulfide in a μ4-S binding mode and the sulfide is in a distorted tetrahedral geometry with the four iron atoms at each corner of the distorted tetrahedral.In its solid state,two types of non-classic intermolecular hydrogen bonding interactions plus a weak π-π stacking interaction led to a 2-D network.  相似文献   

6.
王凤武  魏亦军  朱其永 《结构化学》2007,26(11):1327-1331
A Schiff base zinc(Ⅱ) complex [Zn(C12H16BrClN2O)2(NCS)2] was prepared and characterized by elemental analysis,IR and single-crystal X-ray diffraction. The crystal belongs to the triclinic system,space group P1 with a=8.414(1),b=9.124(1),c=22.212(3),α=79.177(2),β=86.296(2),γ=89.899(2)o,V=1671.3(4)3,Z=2,Dc=1.631 g/cm3,Mr=820.79,λ(MoKα)= 0.71073,μ=3.444 mm-1,F(000)=824,R=0.0646 and wR=0.1179. A total of 7371 unique reflections were collected,of which 3904 with I > 2σ(I) were observed. The complex crystallizes with two half-molecules per asymmetric unit and each mononuclear molecule is centrosymmetric. The Zn atom lying at the inversion centre is six-coordinated in a slightly distorted octahedral geometry by two phenolate O atoms and two imine N atoms from two Schiff base ligands,as well as two N atoms from two thiocyanate anions. In the crystal structure,the combination of π-π stacking interactions and intermolecular hydrogen bonds (N–H…Br,N–H…O,N–H…N,C–H…O,C–H…S and C–H…Cl) leads to a three-dimensional network.  相似文献   

7.
Aryl selenoamides react smoothly with a-haloacetic acid in various alcohol to givecorresponding bis(carboxyalkylmethyl) diselenides in good yields.  相似文献   

8.
郎建平  蔡进华 《结构化学》1995,14(4):297-299
StructureofCopper(Ⅱ)Bis(piperidyldithiocarbamate)LangJian-ping;LuJian-Mei;BianGuo-Qing(DepartmentofChemistry,SuzhouUniversity...  相似文献   

9.
李秀梅  王庆伟  李丹  赵霞  高广刚 《结构化学》2007,26(11):1341-1344
A new one-dimensional copper coordination polymer chain has been prepared and fully characterized by single-crystal X-ray diffraction,elemental analyses and IR spectroscopy. The compound {[Cu2(C2O4)2(inta)4](inta)}n1 crystallizes in the triclinic system,space group P1,with a=8.4722(5),b=10.9825(6),c=11.6128(6),α=104.8050(10),β=102.5740(10),γ= 109.6890(10)o,V=927.18(9)3,Mr=929.79,Z=1,Dc=1.665 g/cm3,F(000)=475,μ=1.231 mm-1,R=0.0453 and wR=0.1185 for 3290 observed reflections (I > 2σ(I)). Of the compound,the Cu center is octahedrally coordinated with oxalate acting as a tetra-dentate ligand coordinated to the copper atom and each inta serving as a terminal ligand by employing only one N-donor to coordinate with the Cu center. An infinite {Cu2(C2O4)2}∞ chain is formed along the c axis. Furthermore,the 1D chains are held together via extensive hydrogen-bonding interactions to generate a three-dimensional network with 1D channels (ca. 5.491×11.507) where inta molecules are filled.  相似文献   

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11.
王家喜  杨德育 《结构化学》1996,15(6):473-477
用X-射线晶体结构衍射法测定了双[1-苄基-1-乙基丙基环戊二烯基]二氯化锆[η5-C5H4C(C2H5)2CH2C6H5]2ZrCl2(I)及(1,2-二异丁基-1,2-甲基-乙基桥联)双环戊二烯基二氯化锆[η5-C5H4C(CH3)(C4H9-i)C(CH3)(C4H9-i)C5H4-η5]ZrCl2(Ⅱ)的结构。二者皆为单斜晶系,(I)的空间群为P2/n,a=12.582(3),b=7.992(2),c=14.979(3)A,β=101.68(1)°,V=1474.9(9)A3,Mr=612.84,Z=2,Dx=1.38g/cm3,μ=5.69cm(-1),F(000)=640,R=0.033,Rω=0.036。(Ⅱ)的空间群为Cc,a=13.309(3),b=9.591(1),c=16.449(8)A。β=4.83(3)°,V=209.2(2)A3,Mr=458.63,Z=4,Dx=1.456g/cm3,μ=7.77cm(-1),F(000)=952,R=0.051,Rω=0.061。化合物(I)以重叠式存在,两个苄基处于反式。晶体(Ⅱ)以交叉式存在,甲基、异丁基以反式构象存在。  相似文献   

12.
苯硫酚的巯基是一个较强的亲核基团,对α,β-不饱和双键的Michael加成反应已有报道.但是当巯基的邻位存在与其形成氢键的基团时,如果按文献条件进行反应,或者反应无法进行,或者要使用反应条件苛刻的丁基锂,或者使用吡啶等毒性较大的反应溶剂,而且产率较低.本文选择  相似文献   

13.
SynthesisandCrystalStructureofTetrabonzoatoBis(2-Aminothiazol)Dicopper(Ⅱ)WangDong-Mei;HouYi-Min;YangRuiNa;HuXiao-Yuan;XuoBao-...  相似文献   

14.
Colorless single crystals of the title compound were accidentally obtained by a reaction of p-sulfophenylalanine with zinc perchlorate. The crystal structure (monoclinic, P21/c, Z = 4, a = 5.9031(7), b = 13.5404(16), c = 9.7932(8) Å, β = 126.438(5)°, V = 629.74(12) Å3, R1[I>2σ(I)] = 0.0276, wR2(all) = 0.0844) reveals a discrete dinuclear [Zn(OH)(μ-ClO4)(H2O)3]2 in which each perchlorate anion acts as a bidentate bridging linker to bind two Zn atoms whereas the hydroxy group is a terminal group. Thus, the local surrounding around the zinc atom can be best described as a slightly distorted octahedron.  相似文献   

15.
(E)‐2‐(2‐Benzylidenehydrazinylidene)quinoxaline, C15H12N4, crystallized with two molecules in the asymmetric unit. The structures of six halogen derivatives of this compound were also investigated: (E)‐2‐[2‐(2‐chlorobenzylidene)hydrazinylidene]quinoxaline, C15H11ClN4; (E)‐2‐[2‐(3‐chlorobenzylidene)hydrazinylidene]quinoxaline, C15H11ClN4; (E)‐2‐[2‐(4‐chlorobenzylidene)hydrazinylidene]quinoxaline, C15H11ClN4; (E)‐2‐[2‐(2‐bromobenzylidene)hydrazinylidene]quinoxaline, C15H11BrN4; (E)‐2‐[2‐(3‐bromobenzylidene)hydrazinylidene]quinoxaline, C15H11BrN4; (E)‐2‐[2‐(4‐bromobenzylidene)hydrazinylidene]quinoxaline, C15H11BrN4. The 3‐Cl and 3‐Br compounds are isomorphous, as are the 4‐Cl and 4‐Br compounds. In all of these compounds, it was found that the supramolecular structures are governed by similar predominant patterns, viz. strong intermolecular N—H...N(pyrazine) hydrogen bonds supplemented by weak C—H...N(pyrazine) hydrogen‐bond interactions in the 2‐ and 3‐halo compounds and by C—H...Cl/Br interactions in the 4‐halo compounds. In all compounds, there are π–π stacking interactions.  相似文献   

16.
1 INTRODUCTION In the last decade, there has been great interest in the crystal engineering of supramolecular architectures organized by coordinate covalent bonds, hydrogen bonds and their combination owing to their fascinating structural diversity and potential applications as functional materials[1~3]. The self-assembly of coordinate polymers and supramolecules is highly influenced by factors such as ligands, metal ions, the counter ions, solvent, template, reaction temperature, pH va…  相似文献   

17.
Cobalt(Ⅱ) can form complexes with Hdbm in different environments. Hdbm reacted with cobalt nitrate to give complex 1 [Co(dbm)2·2H2O]. When complex 1 reacted with pyridine, α-stilbazole or 4,4′-bipyridine respectively, complex 2 [Co(DBM)2Py2] (Py=pyridine), 3 [Co(DBM)2Sbz2] (Sbz=α-stilbazole) or 4 [Co(DBM)2BPy]n was obtained in turn through metathetical reaction. The coordination modes are octahedral polyhedrons. In the crystal structures, the two dbms take the plane position and two other donor molecules take the axial position. CCDC: 196070 for complex 2; 186859 for complex 3.  相似文献   

18.
Two inclusion compounds of dithiobiurea and tetrapropylammonium and tetrabutylammonium are characterized and reported, namely tetrapropylammonium carbamothioyl(carbamothioylamino)azanide, C12H28N+·C2H5N4S2, (1), and tetrabutylammonium carbamothioyl(carbamothioylamino)azanide, C16H36N+·C2H5N4S2, (2). The results show that in (1), the dithiobiurea anion forms a dimer via N—H...N hydrogen bonds and the dimers are connected into wide hydrogen‐bonded ribbons. The guest tetrapropylammonium cation changes its character to become the host molecule, generating pseudo‐channels containing the aforementioned ribbons by C—H...S contacts, yielding the three‐dimensional network structure. In comparison, in (2), the dithiobiurea anions are linked via N—H...S interactions, producing one‐dimensional chains which pack to generate two‐dimensional hydrogen‐bonded layers. These layers accommodate the guest tetrabutylammonium cations, resulting in a sandwich‐like layer structure with host–guest C—H...S contacts.  相似文献   

19.
1 INTRODUCTION Coordination-driven supramolecular assembly hasattracted great interest in constructing beautiful mo-tifs and developing new materials[1~5]. It is crucial toselect or synthesize suitable bridging organic li-gands[6~10]. The reduced Schiff base N-(2-hydro-xybenzyl)-D,L-amino acid is an excellent ligand forself-assembly with metal ions, not only due to itsprolific coordination sites but also its strong abilityto afford hydrogen bonding from secondary aminegroup and carbox…  相似文献   

20.
Interaction of hexafluorosilicic acid with sulfa drugs sulfathiazole (stz) and sulfalen (2-sulfanilamido-3-methoxypyrazine, sl) results in the crystalline salts of the compositions [stzH]2[SiF6] (I) and [4-H2NO2SPhNH3]2[SiF6] (II). Complex I is characterized by IR, mass spectrometry data and single crystal X-ray diffraction. The crystal structure of I is stabilized by a network of charge-assisted hydrogen bonding. The relationship between the solubility and H-bonding system in I, II and related “onium” hexafluorosilicates is discussed. The formation of complex II, previously reported as an interaction product of hexafluorosilicic acid with 4-aminobenzenesulfonamide (sulfanilamide), is the result of cleavage of the C-N bond in sulfalen in acidic medium.  相似文献   

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