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951.
Xiao‐Yuan Wu Quan‐Guo Zhai Li‐Juan Chen Can‐Zhong Lu 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(6):m261-m263
The title complex, poly[di‐μ3‐oxo‐hepta‐μ2‐oxo‐tetraoxobis(1,10‐phenanthroline)‐μ4‐terephthalato‐dicopper(II)tetramolybdate(VI)], [Cu2Mo4(C8H4O4)O13(C12H8N2)2], represents a novel two‐dimensional copper–molybdate compound with mixed ligands. Tetranuclear molybdenum oxide clusters are joined through corner‐sharing into a ribbon‐like chain, with [Cu(phen)]2+ (phen is 1,10‐phenanthroline) complexes grafted onto either side. The terephthalate ligand lies about an inversion centre and links these chains to form a layer via Cu—O and Mo—O bonds. Face‐to‐face π–π stacking interactions between adjacent phen ligands stabilize the structure. 相似文献
952.
Allylic and benzylic Grignard reagents smoothly open phenylalkynyl-activated cyclic trisubstituted epoxides at the more substituted carbon atom to give secondary alcohols with a chiral quaternary center. These alcohols are good substrates for the construction of enantiomerically pure carbobicyclic scaffolds through intramolecular alkylation. 相似文献
953.
S.H. LiuX.F. Qian J. YinL. Hong X.L. WangZ.K. Zhu 《Journal of solid state chemistry》2002,168(1):259-262
Ag2S nanoparticles in hyperbranched polyurethane matrix were prepared through the in situ reaction with thioacetamide as the sulfur source at room temperature. Transmission electron microscopic analysis revealed a uniform spherical shape for Ag2S nanoparticles, with an average size of about 4-10 nm and a narrow size distribution. X-ray powder diffraction and UV-vis spectroscopy were also used to characterize the obtained nanoparticles 相似文献
954.
共合成了13个未见文献报道的三烃基锡肟衍生物,测定了它们的^1h,(^13C,^119Sn)NMR,IR和MS。结果表明此类化合物为四配位锡单体结构,生物活性测定结果表明部分化合物同时兼有杀菌、杀螨、除草多种活性。 相似文献
955.
Two copper complexes [Cu(TTA)2(4,4′‐azpy)] (1) and [Cu‐(TTA)2(3,3′‐azpy)] (2) (HTTA = 1,1,1‐trifluoro‐3‐(2‐thenoyl)‐acetone, 4,4′‐azpy = 4,4′‐azobispyridine, 3,3′‐azpy = 3,3′‐azobispyridine) were synthesized and characterized. The crystal structures were determined by X‐ray diffraction analysis. The crystal 1 belongs to triclinic with space group P1 , a = 0.8515(2) nm, b = 0.9259(2) nm, c = 0.9468(2) nm, a = 66.126(9)°, β = 79.667(9)°, γ = 90.13(1)°, Z = 1, V = 0.6692(2) nm3, Dc = 3.425 g/cm3, γ = 2.113 mm?1, F(000) = 694, R1 = 0.0594, wR2 = 0.1499. The crystal 2 belongs to monoclinic with space group P21/c, a = 1.0661(2) nm, b = 1.4296(3) ran, c = 1.0041(3) nm, β = 114.50(3)°, V = 1.3926(5) nm3, Z = 2, Dc = 1.646 g/ cm3, μ = 1.015 mm?1, F(000) = 694, R1, = 0.0535, wR2 = 0.1113. In the crystals of complexes 1 and 2, the copper atoms have distorted octahedral symmetry. The two compounds possess very similar one‐dimensional linear chains linked through the rodlike 4,4′‐azpy ligands or 3,3′‐azpy ligands. 相似文献
956.
Chun‐Bo Liu Guang‐Bo Che Chuan‐Bi Li Yun‐Cheng Cui 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(4):m153-m155
An in situ reaction under hydrothermal conditions leads to the formation of the title compound, diaqua(pyridine‐2‐carboxylato)(pyridine‐2,6‐dicarboxylato)indium(II) trihydrate, [In(C6H4NO2)(C7H3NO4)(H2O)2]·3H2O, in which the central InIII atom is seven‐coordinated by one pyridine‐2,6‐dicarboxylate ligand, one pyridine‐2‐carboxylate ligand and two water molecules in a pentagonal–bipyramidal coordination environment. An indium(III)–water chain based on an unusual water pentamer is observed. 相似文献
957.
Ming Li Huazheng Yang Guilong Zhao Lirong Wen Wei Cao Shusheng Zhang 《Journal of heterocyclic chemistry》2005,42(2):209-215
A series of new 2‐aryl‐7‐cyano/ethoxycarbonyl‐6‐methylthio‐1H‐imidazo[1,2‐b]pyrazoles ( 5 ) have been synthesized in moderate to good yields, via a two‐step cyclocondensation procedure of 5‐amino‐4‐cyano/ethoxycarbonyl‐3‐methylthio‐1H‐pyrazole ( 1 ) and α‐bromoacetophenones ( 3 ) or α‐tosyloxyacetophenones ( 2 ), which were prepared by the reactions of acetophenones with [hydroxy(tosyloxy)iodo]benzene (HTIB). The intermediates, 5‐amino‐1‐(aroylmethyl)‐4‐ cyano/ethoxycarbonyl‐3‐methylthio‐1H‐pyrazoles ( 4 ), have been isolated, serving as evidence for the regioselectivity. When utilizing α‐tosyloxy‐acetophenones, the reactions were more eco‐friendly, the reaction time was significantly reduced and the synthetic procedure was more convenient and easier to manipulate. Surprisingly, using potassium carbonate to displace sodium carbonate in the synthesis of 4 , in the case of 1 (R? CN), two novel cyclocondensation products have been isolated and fully characterized, followed by the proposal of a plausible mechanism. 相似文献
958.
Yi‐Zhen Tang Hao Sun Ya‐Ru Pan Xiu‐Mei Pan Rong‐Shun Wang 《International journal of quantum chemistry》2007,107(6):1495-1501
The mechanisms for the reaction of CH3S with NO2 are investigated at the QCISD(T)/6‐311++G(d,p)//B3LYP/6‐311++G(d,p) on both single and triple potential energy surfaces (PESs). The geometries, vibrational frequencies, and zero‐point energy (ZPE) correction of all stationary points involved in the title reaction are calculated at the B3LYP/6‐311++G(d,p) level. More accurate energies are obtained at the QCISD(T)/6‐311++G(d,p). The results show that 5 intermediates and 14 transition states are found. The reaction is more predominant on the single PES, while it is negligible on the triple PES. Without any barrier height for the whole process, the main channel of the reaction is to form CH3SONO and then dissociate to CH3SO+NO. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 相似文献
959.
Wei Sun Yan‐Tuan Li Zhi‐Yong Wu Ning‐Yu Xiao 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(3):m111-m113
In the crystal structure of the title complex, [Ni2(C10H20N4O2)(C12H12N2)2](ClO4)2 or [Ni(dmaeoxd)Ni(dmbp)2](ClO4)2 {H2dmaeoxd is N,N′‐bis[2‐(dimethylamino)ethyl]oxamide and dmbp is 4,4′‐dimethyl‐2,2′‐bipyridine}, the deprotonated dmaeoxd2− ligand is in a cis conformation and bridges two NiII atoms, one of which is located in a slightly distorted square‐planar environment, while the other is in an irregular octahedral environment. The cation is located on a twofold symmetry axis running through both Ni atoms. The dmaeoxd2− ligands interact with each other via C—H⋯O hydrogen bonds and π–π interactions, which results in an extended chain along the c axis. 相似文献
960.
Hui Chen Ming Tang Jinming Gao Xia Chen Zongbo Li 《Chemistry of Natural Compounds》2006,42(5):534-538
The volatile mono-and sesquiterpenes obtained from the needles and resin of Pinus armandi, P. tabulaeformis, and P. bungeana growing in the Qinling, Taibai, and Huanglong Mountain forest ecosystem were analyzed by means of GC-MS. Forty-eight constituents
were identified, and α-pinene, β-pinene, 1R-α-pinene, β-caryophyllene, cadindiene, α-caryophyllene, D-limonene, and 1S-β-pinene were the major components of the mono-and sesquiterpenes in the needles and resin. The components of the volatile
mono-and sesquiterpenes from the needles and resin at Qinling, Taibai, and Huanglong Mountains had remarkable differences
in three pine species, whereas the monopertene content such as α-pinene, β-pinene, D-limonene, and camphene were mostly changed in the growing stage. The intraspecies variation in the different ecosystems
can be attributed to the species’ geography and genetic variation, and even the adaptation of the pine species to different
ecological environments. Moreover, monoterpenes and sesquiterpenes can be induced by the attack of bark beetles, of which
the α-pinene, β-pinene, 1R-α-pinene, 1S-α-pinene, b-myrecene, and β-caryophyllene contents had positive relations with the attacking Dendroctonus armandi and D. valens.
Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 430–433, September–October, 2006. 相似文献