Macroscopic Helical Assembly of One-Dimensional Coordination Polymers: Helicity Inversion Triggered by Solvent Isomerism.

Assembling macroscopic helices with controllable chirality and understanding their formation mechanism are highly desirable but challenging tasks for artificial systems, especially coordination polymers. Here, we utilize solvents as an effective tool to induce the formation of macroscopic helices of chiral coordination polymers (CPs) and manipulate their helical sense. We chose the Ni/-,-BrpempH system with a one-dimensional tubular structure, where -,-BrpempH stands for -,-(1-(4-bromophenyl)ethylaminomethylphosphonic acid).

Macroscopic handedness inversion of terbium coordination polymers achieved by doping homochiral ligand analogues.

Inspired by natural biological systems, chiral or handedness inversion by altering external and internal conditions to influence intermolecular interactions is an attractive topic for regulating chiral self-assembled materials. For coordination polymers, the regulation of their helical handedness remains little reported compared to polymers and supramolecules. In this work, we choose the chiral ligands -pempH (pempH = (1-phenylethylamino)methylphosphonic acid) and -XpempH (X = F, Cl, Br) as the second ligand, which can introduce C-H⋯π and C-H⋯X interactions, doped into the reaction system of the Tb(-cyampH)·3HO (cyampH = (1-cyclohexylethylamino)methylphosphonic acid) coordination polymer, which itself can form a right-handed superhelix by van der Waals forces, and a series of superhelices -1H-, -2F-, -3Cl-, and -4Br- with different doping ratios were obtained, whose handedness is related to the second ligand and its doping ratio, indicating the decisive role of interchain interactions of different strengths in the helical handedness.

From helices to superhelices: hierarchical assembly of homochiral van der Waals 1D coordination polymers.

Chiral transcription from the molecular level to the macroscopic level by self-organization has been a topic of considerable interest for mimicking biological systems. Homochiral coordination polymers (CPs) are intriguing systems that can be applied in the construction of artificial helical architectures, but they have scarcely been explored to date. Herein, we propose a new strategy for the generation of superhelices of 1D CPs by introducing flexible cyclohexyl groups on the side chains to simultaneously induce interchain van der Waals interactions and chain misalignment due to conformer interconversion.

Layer or Tube? Uncovering Key Factors Determining the Rolling-up of Layered Coordination Polymers.

Nanotubular materials have garnered considerable attention since the discovery of carbon nanotubes. Although the layer-to-tube rolling up mechanism has been well recognized in explaining the formation of many inorganic nanotubes, it has not been generally applied to coordination polymers (CPs). To uncover the key factors that determine the rolling-up of layered CPs, we have chosen the Co/-, -Xpemp [Xpemp = (4-X-1-phenylethylamino)methylphosphonic acid, X = H, F, Cl, Br] systems and study how the weak interactions influence the formation of layered or tubular structures.

Controllable Macroscopic Chirality of Coordination Polymers through pH and Anion-Mediated Weak Interactions.

Helical architectures with controllable helical sense bias have recently attracted considerable interest for mimicking biological helices and developing novel chiral materials. Coordination polymers (CPs), composed of metal ion nodes and organic linkers, are intriguing systems showing tunable structures and functions. However, CPs with helical morphologies have rarely been explored so far.

Cobalt(II)-dianthracene Frameworks: Assembly, Exfoliation and Properties.

Metal-organic frameworks containing responsive organic linkers are attractive for potential applications in sensors and molecular devices. Herein we report three cobalt(II) phosphonates incorporating responsive dianthracene linkers, namely, Co (amp H ) (H O)  ⋅ 6H O (MDAF-1), Co (amp )(H O)  ⋅ 2H O (MDAF-2) and Co(amp H ) ⋅ 2H O ⋅ 0.5DMF (MDAF-3), where amp H is pre-photodimerized 9-anthrylmethylphosphonic acid.

Oxyfunctionalization of Alkanes Based on a Tricobalt(II)-Substituted Dawson-Type Rhenium Carbonyl Derivative as Catalyst.

POM-supported metal carbonyl derivatives (PMCDs) represent a family of tremendous potential catalysts owing to their peculiar physical and chemical properties. Yet low-valence transition metal-substituted Dawson-type PMCD catalysts are uncommon. Hence, we synthesized a tricobalt-substituted PMCDs by conventional aqueous solution method, [Na(HO)](NH)[PWOCo(HO)(OH)Re(CO)]·13HO (), and characterized by single crystal X-ray diffraction crystallography, IR, and thermogravimetric analyses (TGA), etc.

Changes in magnetic order through two consecutive dehydration steps of metal-phosphonate diamond chains.

Hydrothermal reactions of the multitopic ligand 1-hydroxy-1-(piperidin-4-yl)methylidenebisphosphonic acid (hpdpH) with cobalt or nickel sulfates afforded two new isostructural metal phosphonates, M (hpdpH)(HO)·4HO [M = Co (Co-10HO), Ni (Ni-10HO)]. Their structures consist of parallel diamond chains of three MO octahedra bridged by the POC tetrahedra. Six of the seven oxygen atoms of the ligand are involved in coordination; for two ligands that amounts to 12 bonds for 3 MO and the remaining six are occupied by terminal water molecules.

Interplay of anthracene luminescence and dysprosium magnetism by steric control of photodimerization.

Systematic control of the intermolecular pair-wise [4 + 4] photocycloaddition of a series of dysprosium phosphonates through fine-tuning of two different phosphonate ligands, one with a bidentate blocker and one with an anthracene antenna, both with alkyl substituents, reveals a size dependent rate. With bulky isopropyl on the diphosphonate blocker little response to UV light is observed. In contrast, compounds with ethyl which has less steric hindrance exhibit almost complete photocycloaddition.

Homochiral iron(ii)-based metal-organic nanotubes: metamagnetism and selective nitric oxide adsorption in a confined channel.

Homochiral iron(ii)-based nanotubular metal phosphonates (R)- and (S)-[Fe(pemp)(H2O)2] [pemp2- = (R)- or (S)-(1-phenylethylamino)methylphosphonate] are reported showing metamagnetism at low temperature. The dehydrated product features coordinatively unsaturated and redox-active metal ion sites that enable it to strongly bind nitric oxide at room temperature.

Dynamic Motion of Organic Ligands in Polar Layered Cobalt Phosphonates.

By introducing the polar methoxy group into phenyl- or benzyl-phosphonate ligands, four cobalt phosphonates with layered structures are obtained, namely, [Co(4-mopp)(H O)] (1), [Co(4-mobp)(H O)] (2), [Co(3-mopp)(H O)] (3), and [Co(3-mobp)(H O)] (4), where 4- or 3-moppH is (4- or 3-methoxyphenyl)phosphonic acid and 4- or 3-mobpH is (4- or 3-methoxybenzyl)phosphonic acid. Compounds 1, 2, and 4 crystallize in the polar space groups Pmn2 or Pna2 , whereas compound 3 crystallizes in the centrosymmetric space group P2 /n. The layer topologies in the four structures are similar and can be viewed as perovskite type, where the edge-sharing [Co O ] rhombi are capped by the PO C groups.

Organometallic functionalized non-classical polyoxometalates: synthesis, characterization and electrochemical properties.

Two monomeric non-classical tellurium-containing heteropolymolybdate-supported metal carbonyl derivatives (NH4)5H3{[Te2Mo12(OH)O44][Mn(CO)3]}·18H2O (1) and (NH4)8{[Te2Mo12(OH)O44][Re(CO)3]}·13H2O (2) have been successfully isolated in good yields. Compounds 1 and 2 are the first two examples of metal carbonyl derivatives of heteromolybdate with tellurium as the central atom. These two compounds have been thoroughly characterized by single-crystal X-ray diffraction, elemental analyses, X-ray powder diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, and UV-Vis spectroscopy.

Immobilization of carbonyl rhenium tripods on the surface of a trinickel-substituted Dawson-type polyoxotungstate.

A monomeric trinickel(ii)-substituted phosphotungstate [H9P2W15O62Ni3]9- ion is stabilized by grafting three {Re(CO)3} organometallic groups on the surface for the first time. Magnetic measurements manifest that the resulting complex, Na(NH4)5[P2W15O56Ni3(H2O)3(μ3-OH)3(Re(CO)3)3]·18H2O (1), displays overall ferromagnetic interactions with the presence of ZFS for Ni2+ at low temperature.

A Monomeric Tricobalt(II)-Substituted Dawson-Type Polyoxometalate Decorated by a Metal Carbonyl Group: [PWOCo(HO)(OH)Mn(CO)].

A monomeric tricobalt(II)-substituted phosphotungstate polyanion, [HPWOCo], is stabilized by the attachement of an organometallic group, {Mn(CO)}, for the first time. The resulting polyoxometalate-supported [Mn(CO)] complex (1) can be used as an efficient catalyst in the cycloaddition of CO with epoxides under mild reaction conditions with pyrrolidinium bromide as a cocatalyst. Besides, magnetic measurements show that the compound exhibits weaker ferromagnetic interactions at low temperature.

Isopentatungstate-supported metal carbonyl derivative: synthesis, characterization, and catalytic properties for alkene epoxidation.

A novel isopentatungstate-supported metal carbonyl derivative KH[(CH3)4N]3{[Re(CO)3]4[(μ2-OH)(μ3-O)(W5O18)]}·6H2O () has been synthesized and characterized. Compound represents the second example of isopolyoxotungstate-supported metal carbonyl derivative. The catalysis of for alkene epoxidation with H2O2 was investigated, and was found to efficiently catalyze the epoxidation of cyclooctene with high conversion (98.