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21.
1 INTRODUCTION The synthesis and study of transition metal com- pounds incorporating organic free radicals directly bound to their coordination sphere are a major re- search aim in the field of molecular magnetism[1]. Exceptional stability, ease of chemical modification and versatility in their coordination properties have made nitroxide free radicals one of the most attrac- tive spin carriers for the design of molecular magne- tic materials[2, 3]. The structures and magnetic prope- rties … 相似文献
22.
1 INTRODUCTION Organic-inorganic hybrid materials and polyoxo-metalates have received much attention because of their intriguing structural diversity and potential applications in molecular adsorption, ion exchange, heterogeneous catalysis and nanotech nology as well as in electrical, magnetic and photochemical areas[1, 2]. One of the important ad- vances in the design of new organic-inorganic hybrid materials is utilizing poly- oxometalates’ coordination ability to produce poly- oxoanio… 相似文献
23.
1 INTRODUCTION The investigation of Shiff base complexes con- taining sulfur and complexes of amino acid Schiff bases[1, 2] has recently aroused considerable interest due to their antiviral, anticancer and antibacterial activities. Taurine, known as 2-aminosulfonic acid, is indispensable to human beings and plays an im- portant role in physiological functions. In this con- tribution, we present the synthesis and crystal struc- ture of a new binuclear Zn(II) dimmer with a tri- dentate Sc… 相似文献
24.
LI Yana b WU A-Qinga b ZHENG Fa-Kuna② GUO Guo-Conga② LU Can-Zhonga HUANG Jin-Shuna a 《结构化学》2005,(11)
1 INTRODUCTION Exploration on the syntheses and properties of car- boxylate complexes, especially aromatic carboxylate complexes, has always been a fascinating and chal- lenging research field for decades either in coor- dination chemistry or in functional materials[1, 2]. Cy- anobenzoic acid (Hcba) possessing two functional coordination groups should display structural diver- sities on the formation of complexes[3~15]. In particu- lar, the copper(II) carboxylate complexes bearing spe- … 相似文献
25.
A novel coordination polymer {[Zn(ts-gln)(bipy)]3H2O}n (ts-glnH2=N-p-toly-sulfonyl-glutamine,bipy=2,2-bipyridine) has been prepared and structurally characterized by X-ray diffraction method. It crystallizes in orthorhombic,space group P212121 with a=8.2622(5),b=16.6244(10),c=18.2807(10) ,V=2510.9(3) 3,C22H28N4O8SZn,Mr=573.91,Z=4,Dc= 1.518 g/cm3,μ(MoKa)=1.115 mm-1,F(000)=1192,the final R=0.0262 and wR=0.0662 for 5691 independent reflections with Rint=0.0240. The zinc(Ⅱ) atom is coordinated by N(3) and N(4) atoms of a bipy molecule,two carboxylate O(1) and O(2A) and amino N(1) atoms of ts-gln ligands,resulting in a square-pyramidal geometry. The title complex consists of an infinite zigzag chain of zinc(Ⅱ) ions linked by the carboxylate of N-p-tolysulfonyl-glutamine. 相似文献
26.
ZHAO Qi-Huaa MA Yong-Pingb WANG Qing-Huab FANG Rui-Binb a 《结构化学》2002,21(5):513-516
1 INTRODUCTION Cadmium (Ⅱ) complexes have been exten- sively studied from both chemical and structural views, mainly due to the capability of cadmium (Ⅱ) (shared by most d10 metal ions) to adopt different modes of coordination determined by the consideration of size, as well as electrostatic and covalent bonding forces[1]. And the field of coordination polymers has witnessed tremendous growth over the last decade[2]. Many coordination polymeric networks have been shown to posses intere… 相似文献
27.
Synthesis and Crystal Structure of a New Zn(II) Nitronyl Nitroxide Complex [Zn(NIT4Py)(PDA)(H_2O)_3]
GAO Dong-Zhaoa WANG Shu-Pinga CHEN Jina LI Li-Cuna b LIAO Dai-Zhenga JIANG Zong-Huia② YAN Shi-Pinga a 《结构化学》2006,25(2)
1 INTRODUCTION Nitronyl nitroxides, independently or in combina- tion with metal ions, have been one of the most wi- dely studied systems in molecular magnetism for understanding radical-radical or metal-radical inte- ractions as well as for synthesizing organic ferroma- gnets and metal-radical magnetic materials[1~4]. Up to now, lots of metal-radical complexes have been reported[5~8]. On the other hand, cooperative inter- molecular interactions, such as coordination bonds, hydrogen bon… 相似文献
28.
WANG Shu-Pinga GAO Dong-Zhaoa LIAO Dai-Zhenga JIANG Zong-Huia② YAN Shi-Pinga LI Li-Cuna b a 《结构化学》2006,(2)
1 INTRODUCTION Pyridyl-substituted nitroxide radicals have at- tracted considerable attention in recent years due to the ability to coordinate with metal ions and act as magnetic couplers, giving rise to new functional ma- terials with particular magnetic and optical prope- rties as well as a variety of structural topologies[1~3]. Considerable efforts have been made in designing and preparing multi-dimensional materials with app- ropriate bridges, such as pseudohalide, dicyanide, dicyanoa… 相似文献
29.
SYNTHESIS OF HYPERBRANCHED CONJUGATIVE POLY(ARYLENEETHYNYLENE)S BY ALKYNE POLYCYCLOTRIMERIZATION 总被引:2,自引:0,他引:2
A series of new hyperbranched poly(aryleneethynylene)s are synthesized by the copolycyclotrimerizations oftetraynes(Ⅰand Ⅱ)with aliphatic monoynes(A-C)catalyzed by tantalum-,niobium-,and cobalt-based catalysts.All thereactions proceed smoothly and soluble polymers of high molecular weights(M_w up to 3.8×10~4)are obtained in high yields(up to 97%). 相似文献
30.
HUA Guo-Pinga ZHU Xiao-Tongb ZHANG Jin-Pengb XU Jia-Ningb WANG Qianb JI Shun-Junc ZHANG Yongc TU Shu-Jiangb② a 《结构化学》2006,25(5):599-603
1 INTRODUCTION Various quinolone derivatives are known to dis- play interesting biological properties ranging from microbial activity to cytotoxicity[1]. They have been reported as antiviral (HIV-1)[2] and antitumor agents[3] as well as used as tubulin[4], topoisomerase[5] and thrombocyte inhibitors[6]. As a member of the quino- lone family, substituted N-phenyl-2-quinolones re-present the structural basis of many biologically active compounds, such as protein kinase inhibitors, immunodu… 相似文献