论文标题:过渡金属-羟基多羧酸配位聚合物的合成、结构与性能研究
Studies on the Syntheses, Structures and Performances of Transition Metal-Hydroxyl Polycarboxylate Coordination Polymers
论文作者 谢凤桐
论文导师 徐吉庆,论文学位 博士,论文专业 无机化学
论文单位 吉林大学,点击次数 235,论文页数 259页File Size3466k
2005-06-01论文网 http://www.lw23.com/lunwen_34394317/ 中药;炮制;配伍;提取;转运;化学变化
Urban Environmental Geochemistry, Urbanization;Environmental Problems; Geochemical Engineering; Sustainable Development
金属-多羧酸配位聚合物具有多种多样的拓扑结构类型,在光学、磁性、催化等诸多领域有着广泛的应用前景。本论文选择具有良好螯合能力、亲水性能及生物特性的羟基多羧酸(苹果酸、柠檬酸和酒石酸)为基本建筑单元,在中温水热(溶剂热)条件下,设计合成了十五个新的具有多维网络结构的过渡金属-羟基多羧酸配位聚合物,X-射线单晶结构分析表明:它们均为首次报道的结构类型,其中的羟基多羧酸配体呈现出多种多样新颖的配位模式。(1) 合成了四个新的以苹果酸为桥联配体的三维配位聚合物(1-4),对它们的合成条件、结构及磁性进行了研究,探讨了羧基配位构型(顺-顺、顺-反和反-反)与磁性的关系。(2) 合成了五个含柠檬酸配体的二维及三维配位聚合物(8-12),其中三例(10-12)是以[M4(cit)4]8-立方烷簇为二级建筑单元、通过六配位或四配位的金属离子桥联而成的类分子筛结构,[M4(cit)4]8-二级建筑单元为首次报道。(3) 利用晶体工程学的原理,设计合成了四个新的包含羟基多羧酸和4, 4"-联吡啶混合配体的三维配位聚合物,羟基多羧酸根键合金属离子形成二维层(5-7)或一维链(13)结构,再通过联吡啶分子连接为三维网络。另外,还合成了由异烟酸桥联银离子形成的一维和二维配位聚合物,异烟酸根呈现出新的配位模式。对以上化合物进行了元素分析、红外光谱、光电子能谱和顺磁共振等表征,并对大部分化合物的热性能和磁学性能进行了研究。讨论了反应物配比、体系的酸碱度及有机溶剂等对化合物类型的影响,对各系列化合物的形成规律进行总结,以逐步实现此类聚合物的半定向合成。金属离子间分别存在着反铁磁性、铁磁性和亚铁磁性等相互作用,对化合物结构和磁性的关系进行了初步探讨。
The coordination polymers of metal-polycarboxylates have diverse topology structures and potential applications in many fields. In this paper, the hydroxyl polycarboxylic acids (malic acid, citric acid and tartaric acid) have been been employed to act as the building units, which have excellent chelating ability, hydrophilic nature and biological properties. Under water-alcohol mixed solvothermal conditions with the mild temperature (160-180oC), fifteen coordination polymers of transition metal-hydroxyl polycarboxylates with two-and three-dimensional structures were designed and synthesized, and three new compounds with nitrogen-containing carboxylates were also obtained. The X-ray single-crystal structures of these compounds were determined and characterized by elemental analysis, IR, XPS and EPR spectra. The thermal analyses and magnetic properties for most of the compounds have also been studied. In these compounds, most of the hydroxyl polycarboxylate ligand exhibit new coordination modes which have not been reported in previous literatures and the antiferromagnetic, ferromagnetic and antiferromagnetic interactions are exist respectively between the metal ions. I Transition metal-malate coordination polymers Four matate-bridging coordination polymers, {[M(Hmal)(H2O)]·H2O}n,M = CoII(1), NiII(2) 0.3CoII/0.7NiII(3) and {[Mn(Hmal)(H2O)2]·H2O}n (4),H3mal = malic acid,have been synthesized from weak acidic solutions by solvothermal technique. Compounds 1 , 2 and 3 are isostructural three-dimensional coordination polymers, and the malate coordinated to the metal ions by adopting μ3-pentadentate mode with all of the five oxygen atoms parcipating in the coordination, which is a type of new mode found firstly by us. Both α-and β-carboxylates adopt the syn-anis confirmation. In compound 4, the malates adopt μ3-tetradentate coordination mode connecting the Mn(II) ions together to generate the two-dimensional layers, which are linked to form three-dimensional network. The magnetic data analysis indicate that compounds 1-4 are antiferromagnetic, ferromagnetic, ferrimagnetic and antiferromagnetic. II Transition metal-malate-4,4′-bipy coordination polymers Three new three-dimensional coordination polymers containing matate and 4,4′-bpy as mixed bridging ligands, [M(Hmal)(4,4′-bipy)0.5]n, M = CoII (5), NiII (6) and 0.3CoII/0.7NiII (7), H3mal = malic acid, have been synthesized from weak acidic solutions by solvothermal technique. Compounds 5-7 possess three-dimensional structures, and the metal ions are interconnected by the malate bridging ligand to form 2D layers, which are linked together by different 4,4′-bipy molecules to form three-dimensional network. The malate act as the μ3-pentadentate ligand in 5-7 as same as in 1-3, but the coordination positions and confirmation are different in them. In compounds 5-7, the α-carboxylates coordinated to the metal ions with anis-anis confirmation and -carboxylates with syn-anis confirmation. The magnetic data analysis indicate that compounds 5 and 7 are antiferromagnetic, and 6 is antiferromagnetic. III Transition metal-citrate coordination polymers Five two-and three-dimensional coordination polymers containing citrate as bridging ligands have been synthesized under solvothermal condition, they are {K[Mn(Hcit)(H2O)]}n (8), {[KMn3(OH)(Hcit)2(H2O)]·2H2O}n (9), {K(H2O)2}4 {[Co(H2O)4]2[Co4(cit)4]}n (10), {[K(H2O)2]2[Co2Co4(cit)4]·2H3O·6H2O}n (11) and {[K(H2O)2]2[M2M4(cit)4]·2H3O·8H2O}n, M = 0.7Co/0.3Ni (12). In compounds 8-12, the citrate ligand coordinate to the metal ions with diverse modes, μ3-pentadentate, μ5-heptadentate, μ4-pentadentate, μ5-octadentate and μ5-octadentate, and they are all new coordination modes which are not found in previous litereatures. Compounds 8 and 9 possess three-dimensional supramolecular networks with potassium ions and hydrogen bond linking the two-dimensional Mn-citrate layered structures, respectively. Compounds 10 and 11 possess porous zeolite–like structures, which are constructed from the [Co4(cit)4]8-cubane clu
|
