Five new Mn(II) metal–organic coordination polymers, [Mn(tbip)(bipy)]n (1), {[Mn(tbip)(dpe)]·1.5H2O}n (2), [Mn(tbip)(bpa)]n (3), [Mn(mip)(bpa)]n (4) and {[Mn3(mip)2(Hmip)2(bpp)2(H2O)2]·2H2O}n (5), were prepared through hydrothermal reactions of Mn(II) acetate with H2tbip (H2tbip = 5-tert-butyl isophthalic acid) or H2mip (H2mip = 5-methylisophthalic acid) in the presence of different dipyridyl co-ligands (bipy = 4,4′-bipyridine, dpe = 1,2-bi(4-pyridyl)ethene, bpa = 1,2-bi(4-pyridyl)ethane and bpp = 1,3-di(4-pyridyl)propane). All these compounds were characterized by elemental analysis, IR spectroscopy and X-ray single-crystal diffraction. The structures of 1 and 2 are constructed of [Mn2(tbip)2]n layers, which consist of alternate left- and right-handed helical chains, and further pillared by bipy or dpe ligands into a 3D porous framework. Interestingly, there are two different sizes of pores in 1 and 2. From the topology point of view, both complexes 1 and 2 exhibit the rare rob network based on the dimeric [Mn(COO)]2 subunits as the 6-connected nodes. The ribbon-like chains having 8- and 16-membered rings in 3 and 4 result from dimeric Mn(II) units bridged by H2tbip or H2mip ligands, which are connected by the flexible dpa into 2D open layers. Complex 5 contains rare isophthalato-bridged trimanganese clusters as building units, which are further linked by mip anions to form a one-dimensional ladder-like chain with less common unidentate coordinated bpp decorated as pendants. The thermal stabilities and X-ray powder diffraction studies indicate that the microporous framework of 2 can keep stable even after the loss of guest water molecules. In addition, dominant antiferromagnetic coupling was observed in compounds 1–3 and 5.

Synthesis, structures and properties of Mn(II) coordination frameworks based on R-isophthalate (R = –CH3 or –C(CH3)3) and various dipyridyl-type co-ligands

A series of ZnII and CdII complexes with a flexible dicarboxylate building block and various heterocyclic co-ligands, formulated as {[Zn2(pda)2(phen)2]·2H2O}n (1), {[Zn(pda)(dpe)]·H2O}n (2), [Zn(pda)(bpp)]n (3), {[Cd2(pda)2(2,2′-bipy)2]·2H2O}n (4), {[Cd(pda)(4,4′-bipy)(H2O)]·H2O}n (5) and {[Cd2(pda)2(bpp)3]·14H2O}n (6) (pda = 1,3-phenylenediacetate, phen = 1,10-phenanthroline, dpe = 1,2-di(4-pyridyl)ethylene, bpp = 1,3-bi(4-pyridyl)propane, 2,2′-bipy = 2,2′-bipyridine, and 4,4′-bipy = 4,4′-bipyridine), have been synthesized and structurally characterized. In 1, the (H2O)8clusters interlink the cyclic coordination dimers to give a 3D network through hydrogen bonding. Both 2 and 3 feature 2D corrugated (4,4) layers, which are of 2-fold interpenetrating for 3. In 4, the dimeric CdII subunits are connected by the 1,3-pda ligands to generate a rampart-shaped 1D chain motif. As for 5, the [Cd(pda)]2 rings are connected by the paired 4,4′-bipy ligands to afford a tube-shaped 1D motif. In contrast to 1–5, complex 6 displays a 3D diamond network and, interestingly, the T5(0)A(0)A(2) water tapes are found to locate in the channels of this 3-D array. A structural comparison of these complexes demonstrates that the characteristics of auxiliary ligands (from chelating to bridging) play a key role in governing the coordination motifs as well as the 3-D supramolecular lattices. Solid-state properties such as photoluminescence and thermal stability of 1–6 have also been studied.

Structural diversity and properties of ZnII and CdII complexes with a flexible dicarboxylate building block 1,3-phenylenediacetate and various heterocyclic co-ligands

Four new coordination polymers, [Ni(isop)(bps)(H2O)]2n·5H2O (1), [Ni(O2N–BDC)(bps)(H2O)]2n (2), [Ni(OH–BDC)(bps)2(H2O)]n (3) and {[Ni2(H2O)(tbip)2(bps)2]}n (4) (bps = 4,4′-dipyridyl sulfide, H2isop= isophthalic acid, O2N–BDC = 5-nitroisophthalic acid, OH–BDC = 5-hydroxyisophthalic acid, H2tbip = 5-tert-butyl isophthalic acid), have been isolated from parallel hydrothermal reactions of Ni(OAc)2·4H2O and bps with isop, O2N–BDC, OH–BDC and H2tbip, respectively.
 Compound 1 is an unusual 2D double layered supramolecular motif generated by hydrogen bonding interactions of two single 2D (4,4) networks. Compound 2 has a highly puckered 2D (4,4) sheet and further stack viaO⋯O intermolecular contacts to form a 3D supramolecular structure.
 Compound 3 features a 2D rectangular grid layer with terminal bps ligands projecting into the interlayer space, leading to a highly interdigitated packing motif and further expansion to generate a 3-D network through interlayer C–H⋯π stacking interactions. Compound 4 contains [Ni2(H2O)]4+ dimers bridged by pairs of ligands into a single 3D diamond network with alternately left-handed and right-handed helical channels. As compared to isop, the coexistence of electron-donating (–OH, –C(CH3)3) or electron-withdrawing (–NO2) groups in the dicarboxylate derivatives has a significant effect on the molecular self-assembly. Variable-temperature magnetic susceptibility measurements reveals the existence of weak ferromagnetic interactions between the nickel centers in 4.

Dicarboxylate anion-dependent assembly of Ni(II) coordination polymers with 4,4′-dipyridyl sulfide

To understand the influence of the pH parameter on crystal growth, six compounds prepared at different pH values have been explored, namely {Cu(H2bptc)(bpa)(μ2-H2O)}n (1) {[Cu3(Hbptc)2(bpa)3(H2O)8]·4H2O}n (2), {[Cu2(bptc)(bpa)2(H2O)]·6.5H2O}n (3), {[Mn2(bptc)(bpa) (μ2-H2O)(H2O)5]·H2O}n (4), {[Co2(bptc)(bpe)(μ2-H2O)(H2O)5]·H2O}n (5) and {[Mn2(bptc)(bpe) (μ2-H2O)(H2O)5]·H2O}n (6) (H4bptc = 3,3′,4,4′- benzophenonetetracarboxylic acid, bpa = 1,2-bis(4-pyridy)ethane and bpe = 1,2-bis(4-pyridy)ethene). The structure of 1 displays a 3D open rhombic framework based on an infinite metal-aqua chain. Compound 2 contains two different motifs: a cationic 1D chain of [Cu(bpa)(H2O)4]2+, and an anionic 2D network of [Cu2(Hbptc)2(bpa)2(H2O)4]2−. Compound 3, a microporous open-framework structure, presents an uncommon 3D, trinodal, 4-connected self-penetrating network. Compounds 4, 5 and 6 present the same arrangement with 4,6-connected 3D networks. Comparing the experimental results, it is clear that the pH value plays a crucial role in the formation of the resulting structures. The thermal stabilities of compounds 1–6 are discussed. The magnetic properties for 2 and 4 are also studied and they both exhibit a weak antiferromagnetic coupling through the O2C–C–C–CO2 bridge and μ2-aqua bridge, respectively.

A series of intriguing metal–organic frameworks with 3,3′,4,4′- benzophenonetetracarboxylic acid: structural adjustment and pH-dependence

1D zigzag chain and 0D monomer Cd(II)/Zn(II) compounds based on flexible phenylenediacetic ligand: Synthesis, crystal structures and fluorescent properties

One novel N-[(3-carboxyphenyl)sulfonyl]glycine (H3L1) ligand (1) was prepared in high yield, and its structure was determined by single-crystal X-ray diffraction. Reaction of H3L1 with Mn(ClO4)2·6H2O at different pH values gave two new dinuclear complexes: [Mn2(HL1)2(phen)4]·16H2O (2) and [Mn2L1(phen)4(H2O)]ClO4·3H2O (3) (phen = 1,10-phenanthroline). Additionally, two copper(II) complexes, [K2Cu(L2)2(H2O)2]n (4) and [CuL2(H2O)]2·2H2O (5), involving another novel ligand, N,N′-(1,3-phenylenedisulfonyl)bis(glycine) (H2L2), were prepared by a one-pot reaction of 1,3-phenylenebis(sulfonyl chloride), glycine, and KOH or triethylamine in the presence of CuII ions. A self-assembled (H2O)30 cluster containing a puckered (H2O)12 ring core was found in 2, which presents a new mode of association of water molecules not predicted theoretically or previously observed experimentally. Furthermore, 2 forms a 2-D supramolecular structure through hydrogen bonding and unique π–π stacking interactions. In 3, there also exist discrete trimeric water clusters. The identity of the base determines the specific structural characteristics of 4 and 5. When potassium hydroxide was used for the synthesis of 4, it led to a 3-D copper(II)–potassium(I) coordination polymer; when triethylamine was used, paddle-wheel dinuclear units of copper(II) carboxylate were produced. Magnetic measurements show that there are weak antiferromagnetic interactions in 2–4. In 5 the χMT vs. T curve shows a minimum at 110 K and a climb from 110 K to 5 K, then a long-range antiferromagnetic ordering occurs, as revealed by a decrease in χMT with T. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Two Novel Flexible Multidentate Ligands for Crystal Engineering: Syntheses, Structures, and Properties of CuII, MnII Complexes with N‐[(3‐Carboxyphenyl)sulfonyl]glycine and N,N′‐(1,3‐Phenylenedisulfonyl)bis(glycine)

Jian‐Ge Wang

Papers

Two Novel Flexible Multidentate Ligands for Crystal Engineering: Syntheses, Structures, and Properties of CuII, MnII Complexes with N‐[(3‐Carboxyphenyl)sulfonyl]glycine and N,N′‐(1,3‐Phenylenedisulfonyl)bis(glycine)