Cimex rufipes

Two coordination networks, {[Co­(34pba)₂]·DMF}_<i>n</i> (<b>1</b> and <b>2</b>), where 34pba is 3-(4-pyridyl)­benzoate, were prepared by solvothermal methods. <b>1</b> is a three-dimensional metal organic framework formed by linking [Co₂(34pba)₈] clusters in a <b>bcu</b> net. <b>2</b> consists of single [Co­(34pba)₄] units in a tetragonal plane net of <b>sql</b> topology. The thermal conditions leading to their selective synthesis were established: 120 °C for <b>1</b> and 75 °C for <b>2</b>. Their structures were solved and their thermal behavior was investigated. Further experiments established the activation energy for the desorption of the DMF molecules entrapped in their framework: 76(6)–106(16) kJ mol^–1 for <b>1</b> and 49(3)–58(3) kJ mol^–1 for <b>2</b>. For <b>1</b>, sorption experiments were carried out to demonstrate the ability of the coordination network to absorb different solvents, and the framework solvatochromic response was also ascertained

Concomitant Metal Organic Frameworks of Cobalt(II) and 3‑(4-Pyridyl)benzoate: Optimized Synthetic Conditions of Solvatochromic and Thermochromic Systems

Two coordination networks, {[Co­(34pba)₂]·DMF}_<i>n</i> (<b>1</b> and <b>2</b>), where 34pba is 3-(4-pyridyl)­benzoate, were prepared by solvothermal methods. <b>1</b> is a three-dimensional metal organic framework formed by linking [Co₂(34pba)₈] clusters in a <b>bcu</b> net. <b>2</b> consists of single [Co­(34pba)₄] units in a tetragonal plane net of <b>sql</b> topology. The thermal conditions leading to their selective synthesis were established: 120 °C for <b>1</b> and 75 °C for <b>2</b>. Their structures were solved and their thermal behavior was investigated. Further experiments established the activation energy for the desorption of the DMF molecules entrapped in their framework: 76(6)–106(16) kJ mol^–1 for <b>1</b> and 49(3)–58(3) kJ mol^–1 for <b>2</b>. For <b>1</b>, sorption experiments were carried out to demonstrate the ability of the coordination network to absorb different solvents, and the framework solvatochromic response was also ascertained

Sorption properties toward environmentally important VOCs of half-sandwich Ru(II) complexes containing perylene bisimide ligands

<p>Two py-functionalized perylene bisimide ligands were synthesized and used to make bimetallic half-sandwich Ru(II) complexes. These were characterized by IR, ¹H NMR, ¹³C CPMAS SSNMR spectroscopy, and elemental analysis. The complexes are wheel-and-axle (waa) compounds, where the axle is the divergent ligand and the wheels are the [(p-cymene)RuCl₂] units. The complexes, but not the free ligands, showed absorption of volatile organic compounds such as toluene and xylenes through heterogeneous solid/gas uptakes. The reactivity is ascribable to the waa geometry, likely by an upset of the high stacking characterizing the crystalline frameworks of the free ligands. The kinetic profiles of the uptake reactions were determined.</p

Hydrogenation of Carbon Dioxide to Formate by Noble Metal Catalysts Supported on a Chemically Stable Lanthanum Rod-Metal–Organic Framework

The conversion of carbon dioxide to formate is of great importance for hydrogen storage as well as being a step to access an array of olefins. Herein, we have prepared a JMS-5 metal–organic framework (MOF) using a bipyridyl dicarboxylate linker, with the molecular formula [La2(bpdc)3/2(dmf)2(OAc)3]·dmf. The MOF was functionalized by cyclometalation using Pd­(II), Pt­(II), Ru­(II), Rh­(III), and Ir­(III) complexes. All metal catalysts supported on JMS-5 showed activity for CO2 hydrogenation to formate, with Rh­(III)@JMS-5a and Ir­(III)@JMS-5a yielding 4319 and 5473 TON, respectively. X-ray photoelectron spectroscopy of the most active catalyst Ir­(III)@JMS-5a revealed that the iridium binding energies shifted to lower values, consistent with formation of Ir–H active species during catalysis. The transmission electron microscopy images of the recovered catalysts of Ir­(III)@JMS-5a and Rh­(III)@JMS-5a did not show any nanoparticles. This suggests that the catalytic activity observed was due to Ir­(III) and Rh­(III). The high activity displayed by Ir­(III)@JMS-5a and Rh­(III)@JMS-5a compared to using the Ir­(III) and Rh­(III) complexes on their own is attributed to the stabilization of the Ir­(III) and Rh­(III) on the nitrogen and carbon atom of the MOF backbone

Reversible Guest Removal and Selective Guest Exchange with a Covalent Dinuclear Wheel-and-Axle Metallorganic Host Constituted by Half-Sandwich Ru(II) Wheels Connected by a Linear Diphosphine Axle

The organometallic unit {[(<i>p</i>-cymene)­RuCl₂]₂­[4,4′-bis­(diphenylphosphino)­biphenylene]} has been revealed to be a good building block for the construction of wheel-and-axle (waa) crystalline scaffolds able to incorporate different organic solvents. In fact, the synthesis carried out in tetrahydrofuran (THF), dichloromethane, toluene, and <i>p</i>-xylene led to the corresponding solvates. An apohost could instead be isolated from diethyl ether. However, this showed a lower crystallinity than the solvates, as usually expected for waa compounds. Thermal extrusion of THF led to a new apohost framework. The desolvation process occurred with partial loss of crystallinity which, however, was completely restored after sorption of THF vapors with rebuilding of the starting THF solvate. THF could also be exchanged with <i>p</i>-xylene by a vapor uptake process, while exposure to other aromatics, such as benzene, toluene, and <i>o</i>- and <i>m</i>-xylene led to partial guest exchanges. The use of a more branched guest, such as <i>p</i>-cymene, completely blocked the exchange. THF could be exchanged also with phenylacetylene and 4-ethynyltoluene, although a final stable host/guest compound was isolated only with the last. The monitoring by X-ray powder diffraction analysis of the <i>p</i>-xylene and phenylacetylene uptakes provided evidence that the exchange processes occur with complete retention of crystallinity, thus pointing out the flexibility of the crystalline networks involved in the aforementioned dynamic processes

Reversible Guest Removal and Selective Guest Exchange with a Covalent Dinuclear Wheel-and-Axle Metallorganic Host Constituted by Half-Sandwich Ru(II) Wheels Connected by a Linear Diphosphine Axle

The organometallic unit {[(<i>p</i>-cymene)­RuCl₂]₂­[4,4′-bis­(diphenylphosphino)­biphenylene]} has been revealed to be a good building block for the construction of wheel-and-axle (waa) crystalline scaffolds able to incorporate different organic solvents. In fact, the synthesis carried out in tetrahydrofuran (THF), dichloromethane, toluene, and <i>p</i>-xylene led to the corresponding solvates. An apohost could instead be isolated from diethyl ether. However, this showed a lower crystallinity than the solvates, as usually expected for waa compounds. Thermal extrusion of THF led to a new apohost framework. The desolvation process occurred with partial loss of crystallinity which, however, was completely restored after sorption of THF vapors with rebuilding of the starting THF solvate. THF could also be exchanged with <i>p</i>-xylene by a vapor uptake process, while exposure to other aromatics, such as benzene, toluene, and <i>o</i>- and <i>m</i>-xylene led to partial guest exchanges. The use of a more branched guest, such as <i>p</i>-cymene, completely blocked the exchange. THF could be exchanged also with phenylacetylene and 4-ethynyltoluene, although a final stable host/guest compound was isolated only with the last. The monitoring by X-ray powder diffraction analysis of the <i>p</i>-xylene and phenylacetylene uptakes provided evidence that the exchange processes occur with complete retention of crystallinity, thus pointing out the flexibility of the crystalline networks involved in the aforementioned dynamic processes

DataSheet1_Chiral “doped” MOFs: an electrochemical and theoretical integrated study.docx

This work reports on the electrochemical behaviour of Fe and Zn based metal-organic framework (MOF) compounds, which are “doped” with chiral molecules, namely: cysteine and camphor sulfonic acid. Their electrochemical behaviour was thoroughly investigated via “solid-state” electrochemical measurements, exploiting an “ad hoc” tailored experimental set-up: a paste obtained by carefully mixing the MOF with graphite powder is deposited on a glassy carbon (GC) surface. The latter serves as the working electrode (WE) in cyclic voltammetry (CV) measurements. Infrared (IR), X-ray diffraction (XRD) and absorbance (UV-Vis) techniques are exploited for a further characterization of the MOFs’ structural and electronic properties. The experimental results are then compared with DFT based quantum mechanical calculations. The electronic and structural properties of the MOFs synthesized in this study depend mainly on the type of metal center, and to a minor extent on the chemical nature of the dopant.</p

Water sorption studies with mesoporous multivariate monoliths based on UiO-66

Hierarchical linker thermolysis has been used to enhance the porosity of monolithic UiO-66-based metal-organic frameworks (MOFs) containing 30 wt% 2-aminoterephthalic acid (BDC-NH2) linker. In this multivariate (i.e. mixed-linker) MOF, the thermolabile BDC-NH2 linker decomposed at ∼350 °C, inducing mesopore formation. The nitrogen sorption of these monolithic MOFs was probed, and an increase in gas uptake of more than 200 cm3 g−1 was observed after activation by heating, together with an increase in pore volume and mean pore width, indicating the creation of mesopores. Water sorption studies were conducted on these monoliths to explore their performance in that context. Before heating, monoUiO-66-NH2-30%-B showed maximum water vapour uptake of 61.0 wt%, which exceeded that reported for either parent monolith, while the highly mesoporous monolith (monoUiO-66-NH2-30%-A) had a lower maximum water vapour uptake of 36.2 wt%. This work extends the idea of hierarchical linker thermolysis, which has been applied to powder MOFs, to monolithic MOFs for the first time and supports the theory that it can enhance pore sizes in these materials. It also demonstrates the importance of hydrophilic functional groups (in this case, NH2) for improving water uptake in materials.</p