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911.
912.
HuaRongZHAO XiaoFengLI XinJianZHAO YangPingNIU 《中国化学快报》2004,15(11):1292-1294
Aryl selenoamides react smoothly with a-haloacetic acid in various alcohol to givecorresponding bis(carboxyalkylmethyl) diselenides in good yields. 相似文献
913.
Michael-Addition Reaction of Malononitrile with a,β-Unsaturated Cycloketones Catalyzed by KF/Al_2O_3
The utility of fluoride salts as potential base in a va-riety of synthetic reactions has been recognized in re-cent years.1 However, low solubility of fluoride salts in ordinary solvents hampers their wide applications in organic synthesis. On the other hand, there has been increasing use of inorganic solid supports as catalysts for many years2 resulting in higher selectivity, milder reaction conditions and easier work-up. Especially po-tassium fluoride-coated alumina (KF-alumina) has been a … 相似文献
914.
Introduction Functional substituted cyclopentadienyl organolan-thanide complexes continue to attract considerable at-tention because these donor-functionalized side chains can increase the stability of highly reactive organolan-thanide complexes by forming the additional in-tramolecular chelating coordination with the central metal, and for early lanthanide complexes, the enhanced stability offers the opportunity to explore the reactivity of the remaining ligands.1-4 In addition, the in-tramol… 相似文献
915.
Zn(Ⅱ)-双呋喃甲醛缩乙二胺配合物的合成、结构和性质 总被引:6,自引:0,他引:6
合成了未见文献报道的双呋喃甲醛缩乙二胺与Zn2 + 的Schiff碱配合物 ,通过单晶X射线衍射法测定了其结构 .晶体属于单斜晶系 ,空间群P2 ( 1) /n ,a =0 8780 ( 11)nm ,b =1 44 61( 18)nm ,c =1 14 95 ( 15 )nm ,α =90° ,β =94 12 1( 18)° ,γ =90° ,V =1 45 6( 3 )nm3 ,Z =4,F( 0 0 0 ) =712 ,μ =2 0 5 1mm-1,R1=0 0 471,wR2 =0 0 85 7.用Gaussian 98程序计算了该配合物的键长、键角、电荷布局和频率 .通过荧光光谱研究了配体与配合物的荧光性质 ,并通过元素分析、红外光谱、热分析对配合物进行了表征 相似文献
916.
Shu Xia LIU* Chun Mei WANG Hong Ju ZHAI De Hui LI En Bo WANG Institute of Polyoxometalate Chemistry Department of Chemistry Northeast Normal University Changchun 《中国化学快报》2004,15(2):216-219
Heteropolyoxometalates are a large family of potent medicines due to their excellent antiviral and antitumor activity 1-4, while their application in clinic meets great difficulties for their toxicity 5. How to synthesize heteropolyoxometalate medicines possessing high activity and low toxicity has become the focus in heteropolyoxometalate medicine research. Previously reported polyoxometalates showing medical activities are all salts simple Na+, K+ or NH4+ etc. inorganic cations, in which o… 相似文献
917.
1 INTRODUCTION The construction of low-dimensional organic- inorganic hybrid material with novel properties re- presents new directions in solid-state chemistry[1, 2]. Generally the physical properties of such low di- mensional compounds differ from tho… 相似文献
918.
0IntroductionConstructionoflow鄄dimensionalorganic鄄inorgan鄄icsupramoleculararrayswithnovelpropertiesrepre鄄sentsnewdirectionsinsolid鄄statechemistry[1,2].Gener鄄allythephysicalpropertiesofsuchlowdimensionalcompoundsdifferfromthoseoftheparentcompound.Our 相似文献
919.
Four lanthanide coordination polymers with benzophenone‐4,4′‐dicarboxylic acid (H2bpndc) and 1,10‐phenanthroline (phen), [Ln2(bpndc)3(phen)] (Ln=La (1), Pr (2) and Tb (3)), [Yb(bpndc)15(phen)].05H2O (4) were obtained through solvothermal synthesis. The crystallographic data show that 1, 2, and 3 are isostructural, the Ln(III) ions in 1, 2 and 3 are all eight‐ and ten‐coordinated, respectively, and thus the Ln(III) ions are connected by bpndc ligands, resulting in an interpenetrating 3D structure. While in 4, the Yb(III) ions are eight‐coordinated and connected by bpndc ligands into a 3D structure with 1D rhombic channels, which result from the effect of lanthanide contraction from La(III) to Yb(III) ions, and the bpndc ligands in 1, 2, 3, and 4 display three types of coordination modes. 相似文献
920.