2，2′-联喹啉-4，4′-二羧酸构筑的一维钴(Ⅱ)配位聚合物

利用2,2′-联喹啉-4,4′-二羧酸钠(Na2bqdc),2,2-联吡啶与硫酸钴在溶剂热作用下合成了1个一维配位聚合物[Co(bqdc)(bipy)(H2O)]n(1)。通过元素分析、粉末衍射、红外、紫外光谱对配合物进行了表征,利用X射线单晶衍射仪测定了其晶体结构。中心CoⅡ离子分别与2个来自2,2-联喹啉-4,4-二羧酸钠配体的双齿羧基氧原子和1个来自配体的单齿羧基氧原子、辅助配体2,2-联吡啶上的2个N原子和1个水分子的氧原子配位,形成了1个稍微扭曲的八面体配位构型。紫外光谱实验表明,相对2,2′-联喹啉-4,4′-二羧酸钠配体,配合物的紫外光谱发生了少量的蓝移。对该配合物多晶样品的差热分析(TGA)表明该化合物在217℃后开始分解。     

两个二维层状4-双(咪唑基-1-甲基)-苯钴和镍配位聚合物的合成与表征

以1,4-双(咪唑基-1-甲基)-苯(bix)为配体,间苯二甲酸(IPA)为辅助配体,合成制备了两种新型同构配位聚合物:{[Ni(bix)(IPA)(H_2O)]}_n(1)和{[Co(bix)(IPA)(H_2O)]}_n(2)。单晶结构表明,此两个配合物均形成二维层状空间结构,金属原子均为六配位八面体结构,赤道平面上四个配位原子来自间苯二甲酸和配位水分子,轴向两个配位原子为bix配体的咪唑环上的N原子。金属原子通过配体连接形成四连接的二维4(4).6(2)方格层状结构。     

2,2'-联喹啉-4,4'-二羧酸构筑的一维钴(Ⅱ)配位聚合物

利用2,2'-联喹啉-4,4'-二羧酸钠(Na2bqdc),2,2-联吡啶与硫酸钴在溶剂热作用下合成了1个一维配位聚合物[Co(bqdc)(bipy)(H20)]n(1).通过元素分析、粉末衍射、红外、紫外光谱对配合物进行了表征,利用X射线单晶衍射仪测定了其晶体结构.中心CoⅡ离子分别与2个来自2,2-联喹啉-4,4-二羧酸钠配体的双齿羧基氧原子和1个来自配体的单齿羧基氧原子、辅助配体2,2-联吡啶上的2个N原子和1个水分子的氧原子配位,形成了1个稍微扭曲的八面体配位构型.紫外光谱实验表明,相对2,2'-联喹啉-4,4'-二羧酸钠配体,配合物的紫外光谱发生了少量的蓝移.对该配合物多晶样品的差热分析(TGA)表明该化合物在217℃后开始分解.     

含2-苯氧基丙酸根的镍、锌配位聚合物的合成与晶体结构

用溶液法和水热法分别合成了2个含2-苯氧基丙酸配体(HL)的聚合物{[NiL2(H2O)2(bipy)].2H2O}n(1)、{[ZnL2(bipy)].2H2O}n(2)(bipy=4,4′-联吡啶),用元素分析、红外光谱、热重和单晶X-射线衍射对产物进行了表征。在化合物1中,镍原子与2个羧基氧原子、2个配位水氧原子及2个4,4′-联吡啶的2个氮原子配位,配位数为6,镍原子的配位构型为畸变的八面体;而在化合物2中,锌原子与2个羧基氧原子及2个4,4′-联吡啶中的2个氮原子配位,锌原子的配位构型为畸变的四面体。在这2个化合物里,4,4′-联吡啶通过氮原子连接金属原子形成一维链状。链间氢键与π-π堆积作用又将一维链链接成二维层状结构。     

一维配位聚合物{[Co(dpa)(H2O)4]·(dpdo)·(H2O)}n(H2dpa=2,2’-联苯二酸,dpdo=N,N’-二氧化-4,4’-联吡啶)的晶体结构和光谱性质

采用水热合成法制备了一个一维配位聚合物{[Co(dpa)(H2O)4].(dpdo).(H2O)}n(1)(H2dpa=2,2′-联苯二酸,dpdo=N,N′-二氧化-4,4′-联吡啶),通过红外光谱、紫外光谱、元素分析、XRPD、TGA和X-射线单晶衍射进行了表征。Co(Ⅱ)原子采取了畸变的八面体构型,6个配位氧原子分别来自于2个dpa2-配体和4个配位水分子。每一个dpa2-配体桥联2个Co髤中心,每一个Co(Ⅱ)原子与2个dpa2-配体配位进而形成了21螺旋链结构。借助溶剂水分子的连接作用,螺旋链之间通过多种O-H…O氢键作用形成了2D网格,通过dpdo和2D网格之间多种类型的氢键作用形成了三维超分子结构。测定了室温下聚合物1的固体荧光光谱。     

一维链状锰配位聚合物的合成、晶体结构与性能研究

本文合成了1个新的一维链状锰的配位聚合物{[Mn(HL)(phen)(H2O)2].1.5H2O}n,(H3L=2-羟基-5-羧基苯磺酸),并且进行了元素分析、红外、热重、荧光、紫外、粉末XRD及单晶X射线衍射等表征及研究。标题化合物属于单斜晶系,C2/c空间群,a=0.840 57(17)nm,b=1.757 5(4)nm,c=2.873 4(6)nm,β=92.54(3)°,V=4.240 7(16)nm 3,Z=4,R=0.027 0。每个Mn(Ⅱ)离子与邻菲咯啉配体的2个N原子、磺酸配体中的1个磺酸基O原子和羧基O原子以及2个配位水分子配位,展示出扭曲的八面体几何构型。2个相邻的Mn(Ⅱ)八面体单元通过1个磺酸基氧原子和1个羧基氧原子连接形成一维链状结构,该一维链进一步通过氢键作用构筑成三维网状结构。     

1,3-二(4-吡啶基)-丙烷与邻苯二甲酸构筑的过渡金属配合物的合成、结构和荧光性质

以1,3-二(4-吡啶基)-丙烷(bpp)和邻苯二甲酸(1,2-H2bdc)为配体,通过水热法合成了过渡金属配合物M2(1,2-bdc)2(bpp)2·2H2O[M=Co(1),Ni(2)]和Cd(1,2-bdc)(bpp)·H2O(3).配合物1和2属单斜晶系P21空间群,具有相似的三维骨架结构.配合物中存在2种配位环境相似的金属中心,每个金属中心采取六配位的畸变八面体构型,与来自2个1,2-bdc配体的3个氧原子和2个bpp配体的2个氮原子以及1个水分子配位.1,2-bdc配体采取单齿/双齿螯合的配位模式将金属离子连接成M1-(1,2-bdc)-M2右手螺旋链.bpp配体采取Trans-Gauche(TG)构型,连接相邻的金属离子形成M1-(bpp)-M1链和M2-(bpp)-M2链.这3种链交织在一起构筑成具有{65.8}拓扑的三维结构.配合物3属单斜晶系P21/c空间群,具有单节点的双层二维结构.Cd(Ⅱ)离子采取七配位的畸变五角双锥体构型,与来自2个1,2-bdc配体的4个氧原子,2个bpp配体的2个氮原子和1个水分子配位.1,2-bdc配体采取双齿螯合/双齿螯合的配位模式将Cd(Ⅱ)离子连接成Cd-(1,2-bdc)-Cd链.bpp配体采取TG构型,连接相邻的Cd(Ⅱ)离子,形成Cd-(bpp)-Cd链.这2种链通过共享Cd(Ⅱ)离子交错排列构筑成二维结构.配合物3显示出强的荧光,最大发射位于408 nm处,对应于配体的π*-π跃迁.不同有机小分子对配合物3的荧光强度有不同程度的影响,苯胺对其有显著的猝灭作用,基于荧光猝灭机理,配合物3可用于选择性检测苯胺分子.     

新型双核配位聚合物Ni2（A`B`T`C`）（phen）2（H2O）4·4H2O的合成及其晶体结构

以A`B`T`C`(2,2’,3,3’-偶氮苯四甲酸)和Phen(邻啡啰啉)为配体,采用溶剂挥发法合成了一种新型双核配位聚合物Ni2(A`B`T`C`)(phen)2(H2O)4.4H2O(1),其结构经X-射线单晶衍射和元素分析表征。1属三斜晶系,空间群P-1,晶胞参数a=9.432(11),b=10.697(12),c=10.751(12),α=87.946(17)°,β=67.756(15)°,γ=76.085(16)°,V=972.6843,Z=12,Dc=4.740 mg.cm-3,μ=4.039 mm-1,F(000)=1 364,R1=0.042 5,ωR2=0.132 9。1中Ni(Ⅱ)与A`B`T`C中的两个羧基氧原子,两个H2O中的两个氧原子和phen中的两个氮原子配位,形成一个畸变的八面体几何构型。Ni(Ⅱ)经配体A`B`T`C桥联形成一维链,链与链之间又通过氢键堆积成三维超分子结构。     

2-氨基对苯二甲酸根及2-咪唑烷酮构筑的镉(Ⅱ)配位聚合物的合成、晶体结构及荧光性质

以一种尿素的衍生物2-咪唑烷酮为溶剂,采用脲热法合成了一个新的配位聚合物[Cd(NH2bdc)(e-urea)]n(1)(H2NH2bdc为2-氨基对苯二甲酸,e-urea为2-咪唑烷酮),并对其结构和荧光性质进行了研究。单晶结构分析结果表明,标题化合物的中心镉(Ⅱ)离子分别与2-氨基对苯二甲酸根配体的羧基氧原子和溶剂氧原子配位形成七配位的变形五角双锥结构。相邻的中心镉(Ⅱ)离子通过溶剂氧原子和配体羧基基团的连接,形成无限的一维链。这些一维的链进一步通过2-氨基对苯二甲酸根配体的连接最终形成了具有一维孔道的三维框架结构。研究表明,该化合物在室温下能发出较强的蓝色荧光。     

基于5-(4-(2,6-二(2-吡啶基)-4-吡啶基)苯氧基)间苯二甲酸的Ni(Ⅱ)和Cd(Ⅱ)配位聚合物的合成与晶体结构

用溶剂热法合成了2个以5-(4-(2,6-二(2-吡啶基)-4-吡啶基)苯氧基)间苯二甲酸(H_2L)为配体的金属-有机配位聚合物:{[NiL(H_2O)]·H_2O}_n(1),[Cd L(phen)]_n(2)。通过X-射线单晶衍射,元素分析和红外光谱进行了结构表征。结构分析表明,在1中,L~(2-)配体的2个羧基氧原子桥连相邻的2个Ni(Ⅱ)离子,形成平行于a轴的一维链,链间则通过吡啶氮原子与金属离子连接,最终形成具有(4,4)-连接三维网络结构。在2中,Cd(Ⅱ)为七配位的单帽三棱柱几何构型,L2-配体通过2个羧基和1个吡啶基与3个中心金属Cd(Ⅱ)相连,形成(3,3)-连接的二维层面结构,又通过面间的π…π堆积作用形成了3D超分子结构。测定了配位聚合物的热稳定性和2的荧光性质。     

The ligand, the metal and the 'Holey'-host: Synthesis, structural and magnetic characterisation of Co(II), Ni(II) and Mn(II) metal-organic frameworks incorporating 4,4'-dicarboxy-2,2'-bipyridine

We report herein the single crystal structures of four metal-organic framework complexes incorporating the 4,4'-dicarboxy-2,2'-bipyridine ligand, H(2)dcbp: alpha-[Co(dcbp)(H(2)O)(2)], 1; beta-[Co(dcbp)(H(2)O)(2)], 2, [Ni(dcbp)(H(2)O)(2)], and [[Mn(dcbp)].1/2DEF], 4 (DEF = diethylformamide). In each complex the ligand is deprotonated giving neutral species with 1:1 stoichiometry that form three-dimensional coordination polymers. Supramolecular isomerism (polymorphism) in 1 and 2 arises from the different ligand connectivity around the octahedral Co(II) centres. The two coordinated water molecules in 1 occupy cis positions, which are trans to the chelating bipyridine nitrogen atoms, leaving the carboxylate oxygen atoms in axial trans positions. In 2 all like donors occupy cis positions. Different modes of carboxylate coordination in 1 and 2 give dissimilar network topologies. A rare example of two interpenetrating 6(4)8(2)-b (quartz-like) chiral networks in 1 results from both dcbp carboxylate groups coordinating in a monodentate fashion to adjacent Co(II) centres, whereas in 2 only one carboxylate group bridges between adjacent Co(II) centres giving rise to a single chiral (10,3)-a net. In 1 and 2 the coordinated water molecules hydrogen bond to the non-coordinated carboxylate oxygen atoms. These interactions give rise to water-carboxylate double helices in , and support the coordination network in 2. Strikingly for a pair of dimorphs the crystal densities of 1 and 2 differ by ca. 0.3 g cm(-3)(1.654 vs. 1.940 g cm(-3), respectively). Compound 3 is isomorphous with 1 and likewise features two chiral interpenetrating nets of quartz topology. In 4, chelating bipyridine nitrogen atoms and four carboxylate oxygen atoms from a total of five adjacent dcbp ligands provide distorted octahedral geometry around Mn(II). The carboxylate groups bridge adjacent Mn(II) centres to produce bis-carboxylato chains which cross-link and generate a 3D network that is perforated with channels. The channels are occupied with disordered DEF molecules. The network topology in 4 is quite different to 1-3 and has a (4.6(2))(4(2).6)(4(3).6(6).8(6)) Schlafli notation. Magnetic susceptibility studies performed on 1, 2, [[Mn(dcbp)].1/2DMF] 5 (DMF = dimethylformamide) and [[Mn(dcbp)].2H(2)O] 6 reveal very weak antiferromagnetic coupling between the metal centres in each case.     

一维链状4-乙基苯甲酸镧配合物[La(EBA)_3(EBAH)(H_2O)]_n的合成、晶体结构和性质研究(英文)

水热法合成了配位聚合物[La(EBA)3(EBAH)(H2O)]n(EBA=4-乙基苯甲酸根,EBAH=4-乙基苯甲酸),并通过X-射线衍射单晶结构分析、红外光谱、紫外光谱、荧光光谱以及热重分析对配合物进行了结构和性质研究。配合物属三斜晶系,P1空间群。该配合物具有一维链状结构。La3+离子与9个O原子配位,其中4个O原子来自4个双齿桥联的4-乙基苯甲酸根,3个O原子来自2个螯合-桥联的4-乙基苯甲酸根,1个O原子来自1个中性的4-乙基苯甲酸,1个O原子来自配位水分子。La3+离子处于九配位扭变的三帽三角棱柱构型中。相邻La3+离子通过双齿桥联或螯合桥联的4-乙基苯甲酸根联结成一维链状结构。存在于分子内的氢键使一维链状结构更加稳定。由于相邻一维链的苯环间存在弱的π…π堆积作用,使分子沿着a轴堆积形成二维层状结构。同时,标题配合物固体具有光致发光特性,蓝光区的较强发射归于配体的π→π*电子跃迁。     

Heterovalent trinuclear Co(III)-Co(II)-Co(III) complexes with N-(2-Carboxyethyl)salicylaldimines

The heterovalent trinuclear cobalt complexes [Co₂^IIIL₄ ⁱ · Co^II(H₂O)₄] · nXmY (L ⁱ are deprotonated Schiff bases derived from substituted salicylaldehydes and β-alanine; i = 1–3) were obtained and characterized. An X-ray diffraction study of the trinuclear cobalt complex with N-(2-carboxyethyl)salicylaldimine showed that the central Co(II) ion and the terminal Co(III) ions are linked by bridging carboxylate groups. Either terminal Co(III) atom is coordinated to two ligand molecules. They form an octahedral environment consisting of two azomethine N atoms, two phenolate O atoms, and two O atoms of two carboxylate groups. The central Co(II) atom is coordinated to four water molecules and to two O atoms of two bridging carboxylate ligands involved in the coordination sphere of the terminal Co(III) atoms.     

Syntheses and characterization of six coordination polymers of zinc(II) and cobalt(II) with 1,3,5-benzenetricarboxylate anion and bis(imidazole) ligands

Six new coordination polymers, namely [Zn1.5(BTC)(L1)(H2O)2].1.5H2O (1), [Zn3(BTC)2(L2)3] (2), [Zn3(BTC)2(L3)1.5(H2O)].H2O (3), [Co6(BTC)4(L1)6(H2O)3].9H2O (4), [Co1.5(BTC)(L2)1.5].0.25H2O (5), and [Co4(BTC)2(L3)2(OH)2(H2O)].4.5H2O (6), where L1 = 1,2-bis(imidazol-1-ylmethyl)benzene, L2 = 1,3-bis(imidazol-1-ylmethyl)benzene, L3 = 1,1'-(1,4-butanediyl)bis(imidazole), and BTC = 1,3,5-benzenetricarboxylate anion, were synthesized under hydrothermal conditions. In 1-6, each of L1-L3 serves as a bidentate bridging ligand. In 1, BTC anions act as tridentate ligands, and compound 1 shows a 2D polymeric structure which consists of 2-fold interpenetrating (6, 3) networks. In compound 2, BTC anions coordinate to zinc cations as tridentate ligands to form a net with (64.82)2(86)(62.8)2 topology. In compound 3, BTC anions act as tetradentate ligands and coordinate to zinc cations to form a net with (4.62.83)2(8.102)(4.6.83.10)2 topology. In compound 5, each BTC anion coordinates to three Co cations, and the framework of 5 can be simplified as (64.82)2(62.82.102)(63)2 topology. For 4 and 6, the 2D cobalt-BTC layers are linked by bis(imidazole) ligands to form 3D frameworks. In 6, the Co centers are connected by micro3-OH and carboxylate O atoms to form two kinds of cobalt-oxygen clusters. Thermogravimetric analyses (TGA) for these compounds are discussed. The luminescent properties for 1-3 and magnetic properties for 4-6 are also discussed in detail.     

Novel Pb(II), Zn(II), and Cd(II) coordination polymers constructed from ferrocenyl-substituted carboxylate and bipyridine-based ligands

Treatment of two kinds of ferrocenyl-substituted carboxylate ligands (3-ferrocenyl-2-crotonic acid, HOOC-CH=(CH(3))CFc (Fc=(eta(5)-C(5)H(5))Fe(eta(5)-C(5)H(4))) or O-ferrocecarbonyl benzoic acid, o-HOOCC(6)H(4)COFc with Pb(OAc)(2).3H(2)O, Zn(OAc)(2).2H(2)O, or Cd(OAc)(2).2H(2)O) resulted in four novel ferrocene-containing coordination polymers [[Pb(mu(2)-eta(2)-OOCCH=(CH(3))CFc)(2)].MeOH](n) (1), [[Zn(o-OOCC(6)H(4)COFc)(2)(4,4'-bipy)(H(2)O)(2)].2MeOH.2H(2)O](n) (4,4'-bipy = 4,4'-bipyridine) (2), [[Cd(o-OOCC(6)H(4)COFc)(2)(bpe)(MeOH)(2)].2H(2)O](n) (bpe = 1,2-bis(4-pyridyl)ethene) (3), and [Pb(o-OOCC(6)H(4)COFc)(eta(2)-o-OOCC(6)H(4)COFc)(bpe)](n)() (4). Their crystal structures have been characterized by single X-ray determinations. In polymer 1, Pb(II) ions are bridged by tridentate FcC(CH(3))=CHCOO(-) anions, forming an infinite chain [Pb(mu(2)-eta(2)-OOC=CH(CH(3))CFc)(2)](n). In polymers 2-4, there are three kinds of components, metal ions, o-FcCOC(6)H(4)COO(-) units, and organic bridging ligands. The bipyridine-based ligands connect metal ions leading to a one-dimensional chain with o-FcCOC(6)H(4)COO(-) units acting as monodentate or chelate ligands in the side chain. Such coordination polymers containing ferrocenyl-substituted carboxylate and bipyridine-based ligands are very rare. The solution-state differential pulse voltammetries of polymers 1-4 were determined. The results indicate that the half-wave potential of the ferrocenyl moieties is influenced by the Pb(II) ions in polymer 1 and strongly influenced by Zn(II), Cd(II), or Pb(II) ions in polymers 2-4. The thermal properties of the four polymers were also investigated.     

Co-ligand-directed structural and magnetic diversities in an anisotropic Co(II)-triazolate system

Three novel 3,5-diamino-1,2,4-triazole (Hdatrz)-based Co(II) coordination complexes, [Co(Hdatrz)(0.5)(H(2)O)(2)(btec)(0.5)](n) (1), {[Co(Hdatrz)(Hbtc)]·H(2)O}(n) (2) and [Co(2)(datrz)(2)(nb)(2)](n) (3) (H(4)btec = 1,2,4,5-benzenetetracarboxylic acid, H(3)btc = 1,3,5-benzenetricarboxylic acid and Hnb = 4-nitrobenzoic acid), were synthesized by incorporating different carboxylate-containing co-ligands and then were structurally and magnetically characterized. Complex 1 is a 3D pillared-layer framework with corrugated Co(II)-btec(4-) layers supported by neutral μ(2)-N1, N4-Hdatrz ligands. In contrast, the other two complexes are chiral (4, 4)- and racemic (4, 8(2))-topological layers with asymmetric μ(2)-N1, N4-Hdatrz-bridged helical chains extended by bis-monodentate Hbtc(2-) ligands for 2 and with a μ(3)-N1, N2, N4-datrz((-)) aggregated Shastry-Sutherland magnetic layer for 3. More interestingly, different magnetic phenomena with a field-induced metamagnetic transition from antiferromagnetic ordering to a ferromagnetic state for 1, spin-canted antiferromagnetism with a T(N) lower than 2.0 K for 2, as well as the coexistence of spin frustration and spin-flop transitions for 3 were observed, which, significantly, are governed by the local low-dimensional magnetic motifs mediated by the carboxylate and/or triazolate heterobridges in the anisotropic Co(II)-triazolate system.     

含氟二羧酸和含氮配体与过渡金属(Ⅱ)配合物的合成、表征及晶体结构

水热法合成了5个新的配位聚合物:[Cd(TFSA)(2,2’-bpy)2]n(1),[Mn(HFGA)(phen)2]n(2),[Co(TFSA)(bpp)2(H2O)2]n(3),[Zn(TFSA)(bpp)2(H2O)2]n(4)和[Cu(HFGA)(phen)]n(5)(TFSA=四氟丁二酸,HFGA=六氟戊二酸,2,2’-bpy=2,2’-联吡啶,phen=1,10-邻菲啰啉,bpp=1,3-二吡啶基丙烷),通过X射线单晶衍射确定了配合物的晶体结构.配合物1和2具有相似的1D链结构,四氟丁二酸和六氟戊二酸以两个单齿羧基氧原子分别配位于Cd2+和Mn2+离子,2,2’-联吡啶和1,10-邻菲啰啉分别螯合配位于Cd2+和Mn2+离子.配合物3和4具有相似的1D链结构,1,3-二吡啶基丙烷以两个端基氮原子桥联金属离子,四氟丁二酸和六氟戊二酸分别以单齿方式配位.配合物5是具有{4.82}拓扑的2D网结构,六氟丁二酸配体通过单齿/双齿-桥联模式连接Cu2+离子.5个配合物均通过分子间弱作用进一步构筑成3D超分子结构.     

Helical-chain copper(II) complexes and a cyclic tetranuclear copper(II) complex with single syn-anti carboxylate bridges and ferromagnetic exchange interactions

Tridentate Schiff-base carboxylate-containing ligands, derived from the condensation of 2-imidazolecarboxaldehyde with the amino acids beta-alanine (H2L1) and 2-aminobenzoic acid (H2L5) and the condensation of 2-pyridinecarboxaldehyde with beta-alanine (HL2), D,L-3-aminobutyric acid (HL3), and 4-aminobutyric acid (HL4), react with copper(II) perchlorate to give rise to the helical-chain complexes [[Cu(mu-HL1)(H2O)](ClO4)]n (1), [[Cu(mu-L2)(H2O)](ClO4).2H2O]n (2), and [[Cu(mu-L3)(H2O)](ClO4).2H2O]n (3), the tetranuclear complex [[Cu(mu-L4)(H2O)](ClO4)]4 (4), and the mononuclear complex [Cu(HL5)(H2O)](ClO4).1/2H2O (5). The reaction of copper(II) chloride with H2L1 leads not to a syn-anti carboxylate-bridged compound but to the chloride-bridged dinuclear complex [Cu(HL1)(mu-Cl)]2 (6). The structures of these complexes have been solved by X-ray crystallography. In complexes 1-4, roughly square-pyramidal copper(II) ions are sequentially bridged by syn-anti carboxylate groups. Copper(II) ions exhibit CuN2O3 coordination environments with the three donor atoms of the ligand and one oxygen atom belonging to the carboxylate group of an adjacent molecule occupying the basal positions and an oxygen atom (from a water molecule in the case of compounds 1-3 and from a perchlorate anion in 4) coordinated in the apical position. Therefore, carboxylate groups are mutually cis oriented and each syn-anti carboxylate group bridges two copper(II) ions in basal-basal positions with Cu...Cu distances ranging from 4.541 A for 4 to 5.186 A for 2. In complex 5, the water molecule occupies an equatorial position in the distorted octahedral environment of the copper(II) ion and the Cu-O carboxylate distances in axial positions are very large (>2.78 A). Therefore, this complex can be considered as mononuclear. Complex 6 exhibits a dinuclear parallel planar structure with Ci symmetry. Copper(II) ions display a square-pyramidal coordination geometry (tau = 0.06) for the N2OCl2 donor set, where the basal coordination sites are occupied by one of the bridging chlorine atoms and the three donor atoms of the tridentate ligand and the apical site is occupied by the remaining bridging chlorine atom. Magnetic susceptibility measurements indicate that complexes 1-4 exhibit weak ferromagnetic interactions whereas a weak antiferromagnetic coupling has been established for 6. The magnetic behavior can be satisfactorily explained on the basis of the structural data for these and related complexes.     

Manganese(II)-carboxylate-pseudohalide systems derived from 1,4-bis(4-carboxylatopyridinium-1-methylene)benzene: structures and magnetism

The reactions of manganese(II) acetate or perchlorate, sodium azide or sodium cyanate, and the zwitterionic dicarboxylate ligand 1,4-bis(4-carboxylatopyridinium-1-methylene)benzene (L) under different conditions yielded three different Mn(II) coordination polymers with mixed carboxylate and azide (or cyanate) bridges: {[Mn (L(1))(0.5)(N(3))(OAc)]·3H(2)O}(n) (1), {[Mn(4)(L(1))(N(3))(8)(H(2)O)(4)(CH(3)OH)(2)]·[L(1)]}(n) (2), and {[Mn(3)(L(1))(NCO)(6)(H(2)O)(4)]·[L(1)]·[H(2)O](2)}(n) (3). The compounds exhibit diverse structures and magnetic properties. In 1, the 1D uniform anionic [Mn(N(3))(COO)(2)](n) chains with the (μ-EO-N(3))(μ-COO)(2) triple bridges (EO = end-on) are interlinked by the dipyridinium L ligands into highly undulated 2D layers. Magnetic studies on 1 reveal that the mixed triple bridges induce antiferromagnetic coupling between Mn(II) ions. Compounds 2 and 3 consist of 1D neutral polymeric chains and co-crystallized zwitterions, and the chains are formed by the L ligands interlinking linear polynuclear units. The polynuclear unit in 2 is tetranuclear with (μ-EO-N(3))(2) as central bridges and (μ-EO-N(3))(2)(μ-COO) as peripheral bridges, while that in 3 is trinuclear with (μ-NCO)(2)(μ-COO) bridges. Magnetic studies demonstrate that the magnetic coupling through the mixed azide/isocyanate and carboxylate bridges in 2 and 3 is antiferromagnetic. An expression of magnetic susceptibility based on a 2-J model for linear tetranuclear systems of classical spins has been deduced and applied to 2.     

具有梯形结构钴(Ⅱ)配位聚合物的合成及晶体结构

Co(NO₃)₂, N-carbazolyacetic acid and 4,4′-bipyridyl can give rise to a novel coordination polymer [CO₂(Cabo)₂(NO₃)₂(4,4′-bipy)₂]_n using a fritted U-tube. Single crystal X-ray diffraction displays in the complex, each Co(Ⅱ) is six-coordinated by two N atoms from different 4,4′-bipyridyl ligands, two O atoms of the bridge from two N-carbazolyacetic acid and two O atoms of one nitrate anion to form a distorted octahedral. Two O atoms of the carboxyl group act as bridge to link two Co(Ⅱ) atoms. The resulting structure is a ladder polymer. CCDC: 211713.