Synthese, Structures, And Property Study Of New Helical Coordination Compounds

The aim of this thesis is to synthesize new helical coordination compounds on the basis of V-shaped ligands, organic drugs, organic N-donor ligands and multi-nuclear metal-oxygen clusters or metal ions, to study the synthetic conditions and rules for these compounds, analysis influence of V-shaped ligands and N-donor chelate ligands on the formation of helical structure, and to explore the relationships between structures and properties for these new compounds.A series of new helical coordination compounds have been synthesized on the basis of hydrothermal technique and structurally characterized by elemental analyses, IR, EPR, XPS, XRPD, TG and single crystal X-ray diffractions. The thermal stabilities, magnetic properties and fluorescent activity of these compounds have been studied.1. Six new helical polyoxometalates have been hydrothermally synthesized on the basis of polyoxovanadates decorated or connected by {MxLy} (M = transition metal ions,L = N-donor chelate ligands) fragments: Cu(phen)V₂TeO₈ (1) Ni(phen)V₂TeO₈ (2) [V₄O₇(HAsO₄)₂(phen)₂] (3) [{CoIII(phen)₂}2V₈O₂₃] (4) [Co(2,2'-bpy)₂V₃O_8.5] (5) [{Zn(2,2'-bpy)}₂V₈O₂₁] (6)Compounds 1 and 2 exhibit a novel 2D chiral layer structure featuring two distinct helices. Compounds 1 and 2 represent the first vanadium tellurites covalently bonded with the metal-organic complex moieties and the two compounds also represent the first example of organic-inorganic hybrid vanadium tellurites containing chiral layer structure. Compound 3 represents the first example of 2D inorganic vanadium arsenate backbone decorated with the directly coordinated organic ligands and the compound also represents the first example of organic-inorganic hybrid vanadium arsenate with helical characters. Compounds 4-6 are three novel 2D inorganic-organic hybrid vanadate complexes containing left-handed and right-handed helical chains. Furthermore, by inspection of the structures of 1-6, it is believed that the L and {MxLy} fragments are important for the formation of the helical structures. In addition, the magnetic properties of compounds 1, 2, and 4 were also investigated.2. Nine new pillared helical-layer coordination polymers have been hydrothermally synthesized on the basis of metal ions or their multi-nuclear clusters connected by V-shaped 3,3',4,4'-benzophenonetetracarboxylate (bptc) and linear 4,4'-bipyridine (bpy) ligands: [Cu₂(bptc)(bpy)₂] (7) [Fe₃(Hbptc)₂(bpy)₃(H₂O)4]·2H₂O (8) [Ni₃(Hbptc)₂(bpy)₃(H₂O)4]·2H₂O (9) [Co₂(bptc)(bpy)(H₂O)]·0.5bpy (10) [Cd₂(bptc)(bpy)(H₂O)2]·H₂O (11) [Cu₂(bptc)(bpy)₂] (7) [Fe₃(Hbptc)₂(bpy)₃(H₂O)4]·2H₂O (8) [Ni₃(Hbptc)₂(bpy)₃(H₂O)4]·2H₂O (9) [Co₂(bptc)(bpy)(H₂O)]·0.5bpy (10) [Cd₂(bptc)(bpy)(H₂O)2]·H₂O (11)Compound 7 is a pillared helical-layer complex featuring four distinct helical chains. Compounds 8 and 9 are isostructural and feature 3D structures formed from the interconnection of arm-shaped helical layers with bpy pillars. Compound 10 is a pillared helical-double-layer complex containing four different types of helices. Compound 11 exhibits a novel 3D covalent framework featuring nanosized tubular channels that are built from helical layers pillared by bptc ligands. The structure of 12 is constructed from {Mn(bptc)(H2O)}n2n- layers, which consist of left- and right-handed helical chains, pillared by [Mn2(bpy)3(H2O)4]4+ complexes into a 3D framework. Compounds 13-15 exhibit interesting 2D helical-double-layer structures. Furthermore, the 3D supramolecular structures of 13-15 are similar to the 3D structure of 12. Therefore, the 3D supramolecular structures of 13-15 can also be considered as being constructed from 2D hydrogen-bonded layers, which consist of {M(bptc)(H2O)2}n2n- ribbons, pillared by [M2(bpy)(H2O)6]4+ complexes. These compounds combine respective merits of pillared-layer and helical structures, which may provide a bridge between pillared-layer and helical systems. In addition, photoluminecent and magnetic properties of these compounds are studied.3. Two self-penetrating networks have been constructed based on binuclear or mononuclear metals as nodes and long V-shaped ligands and linear bpy ligands as links. {[Zn₄(bptc)₂(bpy)₄]·(C₅H₃N)·4H₂O}n (16) {[Cd₂(sdba)₂(bpy)(H₂O)₂]·2H₂O}n (17)Compound 16 adopts a novel 3D framework containing quintuple-stranded molecular braid, 9-fold meso helices and 17-fold interwoven helices, among which the quintuple-stranded molecular braid represents the highest-stranded molecular braid known in the field of coordination polymers and inorganic compounds. Compound 17 is an uncommon self-penetrating 2D network containing pseudo-Borromean links and double-stranded helices. More interestingly, when the strong hydrogen bonds between layers are taken into account, the resulting net of 17 becomes an 8-connected 3D self-penetrating network with an unprecedented (421.67) topology, which represents the highest connected topology presently known in self-penetrating systems. Furthermore, the photoluminescent properties of two compounds were studied.4. A series of new helical metal-drug complexes have been hydrothermally synthesized on the basis of metal ions or their multi-nuclear clusters connected by aromatic polycarboxylate ligands and ciprofloxacin (cfH): [Zn(cfH)(Hbtc)]·H2O (18) [Zn₂(cfH)2(odpa)] (19) [Zn₂(cfH)2(bptc)]·4H₂O (20) [Ca(cfH)₂(1,2-Hbdc)₂]·2H₂O (21) [Mn(cf)₂]·2.5H₂O (22) [Co(cf)₂]·2.5H₂O (23) [Zn(cf)₂]·2.5H₂O (24) [Cd(cf)₂]·2.5H₂O (25) [Mg(cf)₂]·2.5H₂O (26) [Ba₂(cf)₂(1,4-bdc)(H₂O)₂]·H₂O (27) [Sr₆(cf)₆(1,4-bdc)₃(H₂O)₆]·2H₂O (28) [Mn₂(cfH)₂(bptc)(H₂O)₂]·8H₂O (29) [Cd₂(cfH)₂(bptc)(H₂O)₂]·8H₂O (30) [Mn(cfH)(1,3-bdc)] (31) [Co(cfH)(1,3-bdc)] (32) [Zn(cfH)(1,3-bdc)] (33) [Zn₂(cfH)₄(1,4-bdc)](1,4-bdc)·13H₂O (34)Compound 18 is a unique helical metal-cfH complex containing five types of helices. Compound 19 exhibits a novel 2D chiral layer structure featuring three distinct helices, and the compound represents the first example of metal-quinolone complexes containing chiral layer structure. The chiral layer structure of 20 is similar to that of 19. The supramolecular structure of 21 contains left-handed and right-handed hydrogen-bonded helice. Compounds 22-26 exhibit interesting two-dimensional rhombic grids featuring left-handed and right-handed single helice. The structures of 27 and 28 consist of unique two-dimensional arm-shaped layers based on the one-dimensional Ba-O-Ba chains or hexanuclear strontium cluster units. Compounds 29 and 30 are isostructural and feature one-dimensional structures formed from the interconnection of [M2(cfH)2(H2O)2] dimers with bptc ligands. Compounds 31-33 contain double-chain-like ribbons constructed from [M2(cfH)2(CO2)2] dimers and 1,3-bdc. Compound 34 consists of a pair of [Zn(cfH)2]2+ fragments bridged by a 1,4-bdc into a dinuclear dumbbell structure. The successful isolation of these compounds provides new structural information that will aid in understanding the mechanisms of action of the quinolone antibacterial drugs. The fluorescent study on the compounds based on d10 metals and the magnetic properties of compounds 22,23,29 and 31 are also discussed.