环糊精在电化学中的应用

本文对环糊精在电化学中的应用进行了简要的介绍。     

NbC固体表面能带和电子结构的理论研究

采用DFT/BLYP方法对NbC(001)和(111)面的电子结构进行研究。计算结果表明,对于NbC(001)表面,其表面态主要集中于费米能级(EF)下方约4.5eV附近区域,并以表面Nb原子和C原子为主要成分。O2分子在该表面吸附时,趋向于吸附在表面Nb原子上。对于NbC(111)表面,其表面态集中在EF下方0.02.0eV区域,靠近EF的态具有较高的表面活性,其主要成分为表面Nb原子的4dxz/dyz成分。上述结论与光电子能谱实验结果基本一致;但由于金属原子d电子数的差异导致NbC(111)表面态成分与类似的TiC化合物并不相同。     

化合物Mo(CO)~n^+(n=1～6)构型和键离能的密度泛函研究

采用DFT/B3LYP方法研究了化合物Mo(CO)~n^+(n=1～6)的基态可能构型,对于各n值,基态可能构型(电子态)依次为：直线型(^6∑^+),直线型(^6∑~g^+),C~2~υ(^2A~2)或D~3~h(^6A~1),D~4~H(^4A~1~g),C~2~ν(^2B~2)或C~4~ν'(^2B~1),D~3~d(^2A~1~g)。计算结果表明,对于n≥3时,碎片离子的构型与体系自旋多重度关系敏感。进一步计算了Mo－CO键的逐级解离能,计算值与实验结果能较好吻合,并从Mo原子4d和5s轨道杂化角度来解释该键解离能随n值的非单调变化。     

从反应条件看有机反应在POPs合成中的应用

多孔有机聚合物(POPs)是一种完全通过有机共价连接的具有良好的热、化学稳定性以及高的比表面积和永久空隙率的化合物,在气体储存、吸附分离、均相催化、光电材料等领域潜具有潜在的应用前景。将基础有机反应拓展到POPs的合成,不仅可以通过多样的、可调节的合成方法赋予POPs优异的性能,而且极大地促进了POPs的发展,使之成为继沸石、MOFs等之后研究的一大热点。由于POPs具有高的分子量和交联度,合成单体具有大的立体空间结构产生的空间位阻等特点,要求合成条件更为苛刻。Suzuki及Friedel-Crafts烷基化反应作为合成POPs重要的合成方法,本文系统地介绍了这两种方法的历史、反应体系以及近几年在POPs合成中的最新研究进展,希望从合成体系的角度为POPs的设计、合成提供一定的借鉴。     

Synthesis and Crystal Structure of a Heptanuclear Trigonal Prismatic Cluster {PrCu_6} with Glycine and Imidazole as Ligands

A new heptanuclear trigonal prismatic cluster [PrCu6(μ3-OH)3(Gly)6im6](ClO4)6 was synthesized through the self-assembly of Pr^3 , Cu^2 , glycine and imidazole in aqueous solution and characterized by X-ray structure analysis. The compound belongs to the trigonal R3 space groupwith a=b=15.8761(2), c=23.4943(5) A, V=5128.4(1)A^3, Z=3, Dc=1.965 g/cm^3,μ=2.869mm^-1 F(000)=3012, the final R=0.0332 and wR=0.0844 for 3596 independent reflections. In the cation, the Pr3 ion is situated at the center of a prism formed by six copper atoms and coordinates to nine oxygen atoms with a tricapped trigonal prismatic coordination polyhedron. Six glycine ligands and six imidazole terminal ligands participate in constructing the cluster.     

Syntheses and Characterizations of (4-NH2C6H4S)4Sn and [(4-NH2C6H4S)2(4-NH3C6H4S)2Sn]Cl2

1INTRODUCTIONInrecentyears,theresearchesontinsulfidemateri-alshavedrawnchemists’attentionowningtotheirpo-tentialapplicationsasphotovoltaicmaterials,hologra-phicrecordingsystem[1,,solarcontroldevices[3]and2]semiconductormaterials.Ageneralmethodtopreparetinsulfidesisthechemicalvapourdepositionfromdi-scretesimpletin-sulfidecomplexes,suchas(PhS)4Sn,Sn(SCy)4and[CF3(CF2)5S]4Sn[4].Duringoureffortinsynthesizingtin-sulphurcomplexes[5],weobtainedtwomononucleartincomplexes,(4-NH2C6H4S)4Sn1an…     

A 2D Layered Thiostannate:Synthesis and Crystal Structure of [tmdpH_2]Sn_3S_7

A new thiostannate,[tmdpH2]Sn3S7 1(tmdp = 4,4'-trimethylenedipiperidine),has been synthesized under solvothermal conditions and characterized by elemental analysis,IR spectroscopy,and single-crystal X-ray diffraction analysis.In 1,the Sn3S4 secondary incomplete cubane-like building units are bridged by μ2-S atoms to form Sn12S12 rings which are then joined parallelly to the [001] plane,giving the final 2D(Sn3S72-)n layer of(6,3) network.The layers are stacked along the c axis so that 24-membered ring channels are generated,in which the organic cations are accommodated.The compound crystallizes in monoclinic,space group C2/c,with a=23.052(3),b=13.4039(12),c=18.412(2),β=120.112(4)°,V=4921.3(9)3,C13H28N2S7Sn3,Mr=792.86,Z=8,Dc=2.140 g/cm3,F(000)=3056,μ=3.619 mm-1,the final R=0.0488 and wR=0.1125 for 4607 observed reflections with I2σ(I).     

主客体化学新法合成脂肪族α-氨基酸

以脂肪醛、氯仿、氢氧化钾和氨水为原料,利用尿素对直链脂肪醛的主客体包合作用,将尿素作为反向相转移催化剂,与正向相转移催化剂十六烷基三甲基溴化铵协同催化一锅合成脂肪族α-氨基酸,取得了一定的效果,并具有操作简单方便、反应条件温和、不用剧毒物等优点。     

β-环糊精固载相薄层层析法拆分氨基酸D,L-对映体的主客体作用研究

以环氧氯丙烷为交联剂，将β-环糊精（CD）固载在活性轻质SiO2表面上，并作为固定相制作层薄板，用于拆分8个客体氨基酸的D，L-对映异构体，考察了助剂（尿素、脱氧胆酸）、展开剂对层板薄板分离效果的影响。同时对客体进行COPAC半经验优化计算，从超分子作用的观点，阐述氨基酸分子截面直径对D，L-对映异构体分离效果的影响，只有截面直径与空腔内径相当，氨基酸才能被有效包络，它们的对映异构体才能得到较好的层析分离。     

Synthesis and Crystal Structure of a Dinuclear Compound Cu2[（O=PPh2）2N]2（μ-O2PPh2）2

1 INTRODUCTION Transition-metal complexes supported by poly-dentate phosphine ligands have been widely studieddue to the unique photophysical properties andpotential applications as industrial catalysts, mole-cular sensors and drugs[1~3]. As known, oxidation ofphosphine ligands could happen in the synthesisreaction to result in novel complex with unexpectedstructure[4, 5]. For example, the structure of complexFe((OPPh2)2N)3[6] is an octahedral tris-chelate arrange-ment of the oxidized a…