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951.
Yun‐Yu Liu Guang‐Shan Zhu Guo‐Zhen Fan Shi‐Lun Qiu 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):m159-m160
In the title compound, poly[μ5‐pyrazine‐2,3‐dicarboxylato‐cadmium(II)], [Cd(C6H2N2O4)]n or [Cd(pdc)]n, where pdc is the pyrazine‐2,3‐dicarboxylate anion, the CdII atom is six‐coordinated by five carboxylate O atoms and one N atom from five different pdc ligands in a distorted octahedral CdO5N coordination geometry. Two CdII atoms are bridged by carboxylate groups of the pdc ligands to create a dimeric unit. The dimeric units are further connected by the pdc ligands to generate an interesting two‐dimensional structure. 相似文献
952.
Gene‐Hsiang Lee Hsin‐Ta Wang 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(5):m216-m219
N,N′‐Bis(4‐pyridylmethyl)oxalamide, C14H14N4O2, exists as a dimer which is extended into a two‐dimensional network with other dimers through pyridine–amide hydrogen bonds. The crystal structure of the title coordination polymer, {[CoCl2(C14H14N4O2)]·0.5H2O}n, features a one‐dimensional zigzag chain, in which the cobalt ion sits at a twofold symmetry position and adopts a tetrahedral geometry, and the bridging ligand lies on an inversion center and connects to CoII ions in a bis‐monodentate mode. Furthermore, two interwoven chains create a cavity of ca 8.6 × 8.6 Å, which produces a three‐dimensional channel. Water molecules are held in the channel by hydrogen bonds. 相似文献
953.
Chun‐Xiang Wang Zhi‐Feng Li Ping Wang 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(11):m473-m475
In the title compound, [Nd2(C4H4O4)2(C2O4)(H2O)2]n, the flexible succinate anion assumes the gauche conformation and bridges the nine‐coordinate Nd atoms to generate two‐dimensional layers parallel to (010). The coordination polymer layers are linked into a three‐dimensional framework by the rigid oxalate ligands. The oxalate ions are located on a center of inversion. 相似文献
954.
Ming‐Zhong Wang Yan‐Yan Zhang Shun‐Lin Li Xiang‐Hai Cai Xiao‐Dong Luo 《Helvetica chimica acta》2006,89(12):3104-3108
A new norsesquiterpene named eupatorone (= (4S,4aR,6R)‐1‐acetyl‐6‐(acetyloxy)‐4,4a,5,6‐tetrahydro‐4,7‐dimethylnaphthalen‐2(3H)‐one; 1 ) and a new sesquiterpene derivative named 2‐deoxo‐2‐(acetyloxy)‐9‐oxoageraphorone (= (1R,4S,4aR,6R,8aS)‐6‐(acetyloxy)‐3,4,4a,5,6,8a‐hexahydro‐4,7‐dimethyl‐1‐(1‐methylethyl)naphthalen‐2(1H)‐one; 2 ), together with the five known cadinene derivatives 3 – 7 were isolated from the flower of Eupatorium adenophorum (Spreng. ). Their structures were established by extensive NMR experiments, including 1D and 2D NMR. 相似文献
955.
Chun‐Xiang Wang Chen‐Xia Du Zhi‐Feng Li 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(10):m488-m490
In the title compound, [Zn(C17H10N5O)2(H2O)2]·4H2O, cyclic water hexamers forming one‐dimensional metal–water chains are observed. The water clusters are trapped by the co‐operative association of coordination interactions and hydrogen bonds. The ZnII ion resides on a centre of symmetry and is in an octahedral coordination environment comprising two O atoms and two N atoms from two 2′‐(4,5‐diazafluoren‐9‐ylidene)picolinohydrazidate ligands and two water molecules. 相似文献
956.
Cu(I)/Diamine-catalyzed Aryl-alkyne Coupling Reactions 总被引:1,自引:0,他引:1
Ye Feng WANG Wei DENG Lei LIU Qing Xiang GUO 《中国化学快报》2005,16(9):1197-1200
Arylalkynes are important building blocks for the synthesis of natural products,pharmaceuticals,and artificial molecular devices1.They are often synthesized via the Pd-catalyzed Sonogashira coupling reactions between aryl halides and terminal alkynes2,3.Unfortunately,it remains difficult to apply the Sonogashira reaction to industrial scale and/or pharmaceutical synthesis,due to the high cost of Pd and the difficulty in removing the toxic Pd residues from the reaction products.Thus it is wor… 相似文献
957.
Layer-by-layer fluorescent conjugated polyelectrolyte films have been studied. The photoluminescence of conjugate polyelectrolytes was observed to be highly tunable during this film assembly process. Efficient photoinduced electron transfer from thus prepared highly luminescent film to a natural electron-transfer protein cytochrome c has also been observed. 相似文献
958.
Three new alkaloids, longistylumphyllines A–C (1–3), together with the six known alkaloids deoxycalyciphylline B, deoxyisocalyciphylline B, methyl homosecodaphniphyllate, daphnicyclidin A, daphnicyclidin B, and daphnicyclidin F, were isolated from the stems and leaves of Daphniphyllum longistylum. Their structures and relative configuration were elucidated on the basis of spectroscopic data, especially 1D and 2D NMR techniques. 相似文献
959.
960.
Xu‐Cheng Fu Xiao‐Yan Wang Ming‐Tian Li Xiao‐Tao Deng Cheng‐Gang Wang 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):m343-m345
The title complex, {[Cu2(C8H4O4)2(C3H4N2)4(H2O)]·H2O}n, is a three‐dimensional polymer formed through bridging by phthalate dianions of two different CuII cations and a network of O(N)—H⋯O hydrogen bonds. The Cu—O and Cu—N interaction distances are in the ranges 2.0020 (16)–2.4835 (17) and 1.968 (2)–1.9855 (19) Å, respectively. The structure is composed of alternating polymer chains parallel to the c axis, with a shortest Cu⋯Cu distance of 6.3000 (5) Å. 相似文献