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1.
Thenorditerpenoidalkaloidsnotonlyhaveimportantpharmacologicalactivities,butalsomaysetoffalotofinterestingchemicalreactionsl'2.Inthecourseofourstudiesonsearchforhighactivity,lowtoxicitycompoundsandconversionoftheskeletons,aseriesofmodificationsofthesealkaloidshavebeenreported'.Inthepresentpaper,wereportsomechemicalreactionsincludingthedemethoxylation,O-demethylationandoxidation,ofthenorditerpenoidalkaloidspseudaconine1andisotalatizidine7.Treatmentofthenorditerpenoidalkaloidscontainingmethoxylgr…  相似文献   

2.
The syntheses, structures, and magnetic properties of a series of di- and trivalent hydridotris(3,5-dimethylpyrazol-1-yl)borate (Tp*) cyanomanganates are described. Treatment of tris(acetylacetonate)manganese(III) [Mn(acac)(3)] with KTp* and tetra(ethyl)ammonium cyanide affords [NEt(4)][(Tp*)Mn(II)(κ(2)-acac)(CN)] (1), as the first monocyanomanganate(II) complex; attempted oxidation of 1 with iodine affords {(Tp*)Mn(II)(κ(2)-acac(3-CN))}(n) (2) as a one-dimensional chain and bimetallic {[NEt(4)][(Tp*)Mn(II)(κ(2)-acac(3-CN))](2)(μ-CN) (3) as the major and minor products, respectively. A fourth complex, [NEt(4)][(Tp*)Mn(II)(η(2)-acac(3-CN))(η(1)-NC-acac)] (4), is obtained via treatment of Mn(acac(3-CN))(3) with KTp* and [NEt(4)]CN, while [NEt(4)](2)[Mn(II)(CN)(4)] (5) was prepared from manganese(II) trifluoromethanesulfonate and excess [NEt(4)]CN. Tricyanomanganate(III) complexes, [cat][(Tp*)Mn(III)(CN)(3)] [cat = NEt(4)(+), 7; PPN(+), 8], are prepared via sequential treatment of Mn(acac(3-CN))(3) with KTp*, followed by [NEt(4)]CN, or [cat](3)[Mn(III)(CN)(6)] with (Tp*)SnBu(2)Cl. Magnetic measurements indicate that 1, 2, and 4 contain isotropic Mn(II) (S = (5)/(2); g = 2.00) centers, and no long-range magnetic ordering is found above 1.8 K. Compounds 7 and 8 contain S = 1 Mn(III) centers that adopt singly degenerate spin ground states without orbital contributions to their magnetic moments.  相似文献   

3.
5, 15-Diphenylporphyrin (DPP), a novel porphyrin model compound, was always inaccessible in quantities suitable for study1 because the difficulty of synthesis. So that the characteristic of this molecule had not been explored until a novel method developed for the preparation of DPP recently2. Therefore it will be possible for the synthesis of DPP-based photosensitizers, and investigation of their photodynamic properties. Here we reported the synthesis of novel photosensitizers 5, 15-diphe…  相似文献   

4.
The equilibrium geometries, vibrational frequencies, atomization energies, adiabatic electron separations, adiabatic detachment energies (ADE), and adiabatic ionization potentials of the low-lying electronic states for the NaAs4 clusters and its ions were investigated employing the DFT method, and then compared with the photoelectron spectra. According to the computed results, reasonable assignments for the photoelectron spectra of NaAs4^- were suggested.  相似文献   

5.
High molecular weight copoly(ether ketone)s (PEK) based on 4-(4-hydroxyphenyl)-1-phthalazinone (DHPZ)/4,4′-thiobisphenol (TBP)/4,4′-diflourodiphenylketone (DFK) were prepared by nucleophilic substitution polycondensation. The copolymers were characterized by FT- and ^1H-NMR. Thermal properties and solubility of copolymers were studied.  相似文献   

6.
In this paper we will discuss Pauling's classic Eq. (1) that relates bond energies, "D," and electronegativities, "x." Recast to be applicable to enthalpies of formation and reaction, we apply it to the study of hydrogenolysis reactions of dienes, diynes, and alkanes, halogenolysis reactions (with chlorine, bromine, and iodine) and metathetical reactions of organosulfur species (sulfides, sulfoxides, and sulfones). It is with great regret that this equation is found wanting.  相似文献   

7.
《中国化学》2006,24(11):1673-1673
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8.
Reactions of p- and m-diiodobenzenes, p,p'-diiodobiphenyl, and 1,3,5-triiodobenzene with anions derived from dicarbonyl(cyclopentadienyl)iron and pentacarbonylmanganese, catalyzed by palladium complexes, provide a successful route to mono-, di-, and trinuclear -aryl iron and manganese complexes.  相似文献   

9.
1 INTRODUCTION In the energetic material field, extensive attention was paid to insensitive compounds possessing not only high energetic density but also good stability. Previous studies[1] have shown that some small mo- lecular compounds such as azoles are good candi- dates for excellent explosives. For example, explo- sives containing triazole rings have the advantages of less molecular weight, high nitrogen content and density, good thermal stability, low impact sensiti- vity and large …  相似文献   

10.
Two dyads of eosin and porphyrin linked with a semi-rigid (-CH2phCH2-) or flexible (-(CH2)4-) bridge and their reference model compounds were synthesized and characterized The intermoleccular interaction and intramolecular photoinduced singlet energy transfer and electron transfer were studied by their absorp tion spectra,fluorescence emission,excitation spectra and fluorescence lifetime The model compounds,ethyl ester of eosm (EoEt) and porphyrin (PorEt),could form complexes in the ground state.When the eosin moieties in dyads were excited,they could transfer some singlet energy to the porphyrins; in the meantime,they could also ndsce electron transfer between two chromophores.Exciting the porphyrin moieties in dyads could induce electron transfer from eosin moieties to porphyrin moieties.The efficiencies (EnT,ET) and rate constants (kEnT,kET) were related to the polarity of solvents and mutual orientation of the two chromophores in dyads.  相似文献   

11.
A new two-dimensional Cd(Ⅱ) coordination polymer, [Cd(2,5-pdch)(H2O)]n·2n(ClO4)·nH2O (2,5-pdch = pyridine-2,5-dicarbohydrazide), was prepared and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 10.905(2), b = 11.602(1), c = 15.034(2) A, β = 117.794 (10°, V = 1682.8(4A3, Z = 4, C7H13CdCl2NsO12, Mr = 542.52, Dc = 2.141 g/cm^3,/μ = 1.691 mm^-1, F(000) = 1072, 2(MoKa) = 0.71073A, the final R = 0.0608 and wR = 0.1329 for 2972 observed reflections with I 〉 2σ(I). Single-crystal X-ray diffraction analysis reveals that the Cd(Ⅱ) atom displays a distorted pentagonal-bipyramidal geometry coordinated by three N atoms and three O atoms from three different 2,5-pdch ligands, and one water molecule. Interestingly, each two Cd(Ⅱ) atoms are bridged by two carbohydrazide groups of the 2,5-pdch ligands to form a dimeric unit, and such dimeric units are further connected by the 2,5-pdch ligand to generate a two-dimensional (4,4)-network.  相似文献   

12.
肖子敬  刘世雄 《结构化学》2004,23(7):798-802
合成了镉的吡啶-2-磺酸配合物Cd(C5H4NSO3)2(H2O)2 1和锌的吡啶-2-磺酸配合物Zn(C5H4NSO3)2(H2O)2 2。 研究表明, 2个化合物属异质同晶, 均属单斜晶系, 空间群为C2/c. 化合物1晶胞参数为:a = 13.7671(5), b = 7.2778(3), c = 16.1559(9) ? b = 106.656(3)? V = 1550.8(1) 3, Z = 4, Dc = 1.990 g/cm3, m =1.719 mm-1, F(000) = 920, R = 0.0225, wR = 0.0584, 共收集到1759个独立衍射点, 其中I≥2(I)的可观测点为1681个;化合物2晶胞参数为:a = 13.711(1), b = 7.1451(9), c = 15.972(1) , b =107.079(5)? V = 1495.7(3) 3, Z = 4, Dc = 1.855 g/cm3, m = 1.964 mm-1, F(000) = 848, R = 0.0310, wR = 0.0831, 共收集到1707个独立衍射点, 其中I≥2(I)的可观测点为1592个。在2个标题配合物中, Cd2+离子(或Zn2+离子)由2个吡啶-2-磺酸中的2个氮和2个氧以及2个水分子中的2个氧配位形成畸变的N2O4八面体配位构型。每个配合物分子具有晶体学2次旋转轴对称性。配合物分子之间通过许多OH(配位水分子)LO(未配位磺酸根)氢键联结成二维结构网络。  相似文献   

13.
Natarajan S 《Inorganic chemistry》2002,41(21):5530-5537
Hydro/solvothermal reactions of ZnO, HCl, H(3)PO(4), 1,4-diazacycleheptane (homopiperazine), and H(2)O under a variety of conditions yielded three new organic-inorganic hybrid materials, [C(5)N(2)H(14)][Zn(HPO(4))(2)].xH(2)O (x = approximately 0.46), I, [C(5)N(2)H(14)][Zn(3)(H(2)O)(PO(4))(2)(HPO(4))], II, and [C(5)N(2)H(14)][Zn(2)(HPO(4))(3)].H(2)O, III. While I has a one-dimensional structure, II possesses a two-dimensional layered structure, and III has a three-dimensional structure closely related to the ABW zeolitic architecture. All the compounds consist of vertex linking of ZnO(4), PO(4), and HPO(4) tetrahedral units. The fundamental building unit, single four-membered ring (S4R), is present in all the cases, and the observed differences in their structures result from variations in the connectivity between the S4R units. Thus I has a corner-shared S4R forming an infinite one-dimensional chain, II has two corner-shared chains fused through a 3-coordinated oxygen atom forming a strip and a layer with eight-membered apertures, and III has S4R units connected via oxygen atoms to give rise to channels bound by eight T atoms (T = Zn, P) in all crystallographic directions. Crystal data: I, monoclinic, space group = P2(1)/n (No. 14), a = 8.6053(3) A, b = 13.7129(5) A, c = 10.8184(4) A, beta = 97.946(1) degrees, V = 1264.35(8) A(3), Z = 4; II, monoclinic, space group = P2(1)/c (No. 14), a = 11.1029(1) A, b = 17.5531(4) A, c = 8.2651(2) A, beta = 97.922(2) degrees, V = 1595.42(5) A(3), Z = 4; III, monoclinic, space group = P2(1) (No. 4), a = 8.0310(2) A, b = 10.2475(3) A, c = 10.570(3) A, beta = 109.651(1) degrees, V = 819.24(3) A(3), Z = 2.  相似文献   

14.
Reactions of two new tripodal ligands 1,3,5-tris(1-imidazolyl)benzene (4) and 1,3-bis(1-imidazolyl)-5-(imidazol-1-ylmethyl)benzene (5) with metal [Ag(I), Cu(II), Zn(II), Ni(II)] salts lead to the formation of novel two-dimensional (2D) metal-organic frameworks [Ag(2)(4)(2)][p-C(6)H(4)(COO)(2)].H(2)O (6), [Ag(4)]ClO(4) (7), [Cu(4)(2)(H(2)O)(2)](CH(3)COO)(2).2H(2)O (8), [Zn(4)(2)(H(2)O)(2)](NO(3))(2) (9), [Ni(4)(2)(N(3))(2)].2H(2)O (10), and [Ag(5)]ClO(4) (11). All the structures were established by single-crystal X-ray diffraction analysis. Crystal data for 6: monoclinic, C2/c, a = 23.766(3) A, b = 12.0475(10) A, c = 13.5160(13) A, beta = 117.827(3) degrees, Z = 4. For compound 7: orthorhombic, P2(1)2(1)2(1), a = 7.2495(4) A, b = 12.0763(7) A, c = 19.2196(13) A, Z = 4. For compound 8: monoclinic, P2(1)/n, a = 8.2969(5) A, b = 12.2834(5) A, c = 17.4667(12) A, beta = 96.5740(10) degrees, Z = 2. For compound 9: monoclinic, P2(1)/n, a =10.5699(3) A, b = 11.5037(3) A, c = 13.5194(4) A, beta = 110.2779(10) degrees, Z = 2. For compound 10: monoclinic, P2(1)/n, a = 9.8033(3) A, b = 12.1369(5) A, c = 13.5215(5) A, beta = 107.3280(10) degrees, Z = 2. For compound 11: monoclinic C2/c, a = 18.947(2) A, b = 9.7593(10) A, c = 19.761(2) A, beta = 97.967(2) degrees, Z = 8. Both complexes 6 and 7 are noninterpenetrating frameworks based on the (6, 3) nets, and 8, 9 and 10 are based on the (4, 4) nets while complex 11 has a twofold parallel interpenetrated network with 4.8(2) topology. It is interesting that, in complexes 6,7, and 11 with three-coordinated planar silver(I) atoms, each ligand 4 or 5 connects three metal atoms, while in the case of complexes 8, 9, and 10 with six-coordinated octahedral metal atoms, each ligand 4 only links two metal atoms, and another imidazole nitrogen atom of 4 did not participate in the coordination with the metal atoms in these complexes. The results show that the nature of organic ligand and geometric needs of metal atoms have great influence on the structure of metal-organic frameworks.  相似文献   

15.
A new complex,[Cd(L)2(pbda)]n(1,L = 3-(2-pyridyl)-4-(p-methoxyphenyl)-5-(2-thienyl)-1,2,4-triazole,H2pbda = 1,4-benzenedicarboxylic acid),has been hydrothermally prepared and characterized by single-crystal X-ray diffraction,IR spectroscopy,elemental analysis and PXRD.The complex crystallizes in monoclinic,space group P21/c with a = 8.2929(9),b = 21.668(2),c = 10.9940(11) ,β = 90.242(2)o,V = 1975.5(4) 3,Z = 2,C44H32N8O6S2Cd,Mr = 945.30,Dc = 1.589 g/cm3,μ = 0.721 mm-1,S = 1.097,F(000) = 960,the final R = 0.0590 and wR = 0.1045 for 3846 observed reflections(I > 2σ(I)).In the title complex,the rigid bridging pbda2-ligands utilize oxygen atoms of carboxylate groups to coordinate with Cd(II) atoms to form one-dimensional chains which are further interlinked into a three-dimension framework via the intermolecular weak interactions.Photoluminescence study revealed that complex 1 exhibits strong fluorescent emission band in the solid state at room temperature.  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.
The three-dimensional coordination polymer {[Cd(cda)2](2CH3OH}n has been syn- thesized by Na(cda) (cda = carbamyldicyanomethanide anion) and hydrated cadmium perchlorate in methanol solution. The crystal belongs to monoclinic, space group C2/c with a = 15.686(3), b = 8.1650(18), c = 13.119(3) (A), β= 119.334(2)°, V = 1464.8(6) (A)3, Z = 4, C10H12CdN6O4, Mr = 392.66, Dc = 1.780 g/cm3, F(000) = 776 and μ = 1.516 mm-1. The structure was refined to R = 0.0248 and wR = 0.0628 for 1176 observed reflections (I > 2σ(I)). The Cd(II) ion is coordinated by two amide- oxygen and four nitrile-nitrogen atoms from six different cda bridging ligands, forming a three- dimensional structure.  相似文献   

18.
1 INTRODUCTION The construction of supramolecular aggregates has received much attention due to their intriguing network topologies and potential functions as new classes of materials[1, 2]. Multiple noncovalent interac- tions, such as hydrogen bonds, π-π stacking and host- guest ionic interactions, play important roles in the supramolecular assembly of metal ions and organic ligands[3, 4]. In this context the multidentate ligands with conjugated groups are employed as building blocks in…  相似文献   

19.
1 INTRODUCTION The polynitrile-ligands, such as TCNE, TCNB, TCNQ, TCNP, tcm, dca and so on, are of ideal multi-functional bridging ligands. Many complexes with poly-nitriles as bridging ligands and uncoor- dinated ligand (electron acceptors) display dist…  相似文献   

20.
Three novel metal-organic complexes with formulas [Ni(C9N2O2H7)2(CH3OH)2](1),[Zn(C9N2O2H7)2(H2O)2](2) and [Cd(C9N2O2H7)2(CH3OH)2](3) were synthesized by the reactions of Ni,Zn and Cd salts with ethyl 2-benzimidazolylacetate under hydrothermal conditions or layering technique,and characterized by single-crystal X-ray diffraction analysis,IR spec-troscopy,solid-state luminescent properties and thermogravimetric(TG) analysis.The crystal data for these three complexes are as follows:for 1,monoclinic,space group P21/c,a = 9.384(3),b = 9.634(3),c = 11.292(3) ,β = 95.787(5)°,V = 1015.7(5) 3,Z = 2,F(000) = 492,Dc = 1.547 Kg/m3,μ = 1.002 mm-1,the final R = 0.0451 and wR = 0.0900 for 1833 observed reflections with Ⅰ 2σ(Ⅰ);for 2,orthorhombic,space group Pbca,a = 10.031(4),b = 10.379(4),c = 17.525(7),V = 1824.6(12) 3,Z = 4,F(000) = 928,Dc = 1.645 Kg/m3,μ = 1.392 mm-1,the final R = 0.0452 and wR = 0.0996 for 1661 observed reflections with Ⅰ 2σ(Ⅰ);for 3,monoclinic,space group P21/c,a = 9.9114(13),b =10.4852(15),c = 10.4120(14) ,β = 108.453(5)°,V = 1026.4(2) 3,Z = 2,F(000) = 532,Dc = 1.705 Kg/m3,μ = 1.110 mm-1,the final R = 0.0322 and wR = 0.0805 for 1822 observed reflections with Ⅰ 2σ(Ⅰ).In the three complexes,the ethyl 2-benzimidazolylacetate shows the same chelating mode,and the adjacent units are interlinked into a two-dimensional layer through hydrogen-bonds(O-H···O,N-H···O).  相似文献   

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