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Benzene and acetonitrile are two of the most commonly used solvents found in almost every chemical laboratory. Titan is one other place in the solar system that has large amounts of these compounds. On Titan, organic molecules are produced in the atmosphere and carried to the surface where they can mineralize. Here, we report the phase diagram of mixtures of acetonitrile and benzene, and provide an account of the structure and composition of the phases. To mimic the environment on Titan more accurately, we tested the stability of the structure under liquid ethane. The results provide new insights into the structure and stability of potential extraterrestrial minerals. In light of Dragonfly, NASA's upcoming mission to Titan, revisiting the fundamental chemistry of the smallest molecules with modern methods and techniques can have significant contributions to this epochal mission and can open new research directions in chemistry. [ABSTRACT FROM AUTHOR]

Flexible metal–organic frameworks (MOFs) can show exceptional selectivity and capacity for adsorption of CO2. The incorporation of CO2 into flexible MOFs that have Cu2+ coordination centers and organic pillar ligands is accompanied by a distortion of the framework lattice arising from chemical interactions between these components and CO2 molecules. CO2 adsorption yields a reproducible lattice expansion that is enabled by the rotation of the pillar ligands. The structures of Cu2(pzdc)2(bpy) and Cu2(pzdc)2(bpe), CPL-2 and CPL-5, were evaluated using in situ synchrotron X-ray powder diffraction at room temperature at CO2 gas pressures up to 50 atm. The structural parameters exhibit hysteresis between pressurization and depressurization. The pore volume within CPL-2 and CPL-5 increases at elevated CO2 pressure due to a combination of the pillar ligand rotation and the overall expansion of the lattice. Volumetric CO2 adsorption measurements up to 50 atm reveal adsorption behavior consistent with the structural results, including a rapid uptake of CO2 at low pressure, saturation above 20 atm, and hysteresis evident as a retention of CO2 during depressurization. A significantly greater CO2 uptake is observed in CPL-5 in comparison with predictions based on CO2 pressure-induced expansion of the pore volume available for adsorption, indicating that the flexibility of the CPL structures is a key factor in enhancing adsorption capacity. [ABSTRACT FROM AUTHOR]

Sensitized upconversion is explored in three metal–organic frameworks (MOFs) constructed from the anthracene dicarboxylate (ADC) derivatives and zirconium nodes, 9,10-ADC (9,10-MOF), 2,6-ADC (2,6-MOF) and 1,4-ADC (1,4-MOF). Selective excitation of surface-bound Pd(ii) mesoporphyrin IX (PdMP) gives rise to delayed fluorescence (τ = 370 ± 30 ns) from anthracene in the 9,10-MOF. The overall upconversion efficiency of the Pd@9,10-MOF is 0.46 ± 0.05% with a threshold intensity of 104 ± 26 mW cm−2. [ABSTRACT FROM AUTHOR]

Despite being the fifth most abundant element in the atmosphere, neon has never been observed in an organic or metal–organic environment. This study shows the adsorption of this highly unreactive element within such an environment and reveals the first crystallographic observation of an interaction between neon and a transition metal. [ABSTRACT FROM AUTHOR]

A 3D Magnesium MOF PCN-72 has been synthesized from the solvothermal reaction of Mg(NO3)2 and a linear ligand. This MOF has a unique structure with 1-dimensional (1D) channel as well as infinite metal chains, which resembles the topology of MIL-53. It is thermally and moisture stable. In situ powder X-ray diffraction studies reveal its interesting phase transitions under temperature change. Calculation shows that each phase of PCN-72 exhibits unique and unusual thermal expansion properties. After removing coordinated solvent at Mg chains, PCN-72 can selectively adsorb CO2 over N2. [ABSTRACT FROM AUTHOR]

Reaction of 1,8-dilithionaphthalene with [AuCl(Et3P)] or [Au2Cl2(μ-dppm)] (dppm = bis(diphenylphosphinomethane)) in Et2O/THF leads to formation of bis(triethylphosphine)-1,8-diaurionaphthalene (1) and dppm-1,8-diaurionaphthalene (2), respectively. The dppm ligand present in complex 2bridges the two gold centers leading to formation of short intramolecular Au–Au distances of av. 2.85 . Complex 2reacts with AgPF6in THF/CH2Cl2to afford a dicationic Au4Ag2complex which has been isolated as the bis(hexafluorophosphate) salt (3). In this cluster, two molecules of 2sandwich two Ag cations resulting in the formation of a Au2AgAu2Ag six-membered ring in which the metal centers are connected by Au–Au (av. 2.84 ) and Au–Ag (av. 2.75 ) metallophilic interactions. This cluster is further stabilized by short Ag–C interactions involving some of the naphthalene carbon atoms. The luminescence spectra of 2and 3have been recorded. Both complexes display relatively broad emission bands centered at 540 nm which result, at least in part, from the heavy atom induced phosphorescence of the naphthalene chromophore. [ABSTRACT FROM AUTHOR]

The activation and CO2 capture properties of a microporous metal–organic framework with elastic single-molecule traps were systematically investigated. This material shows a unique low-energy gas-purge activation capability, high CO2 adsorption selectivities over various gases and optimized working capacities per energy of 2.9 mmol kJ−1 at 128 °C. [ABSTRACT FROM AUTHOR]

A super-paddlewheel (comprised of two paddlewheels) metal–organic polyhedron (MOP) containing surface hydroxyl groups was synthesized and characterized. Condensation reactions with linear alkyl anhydrides lead to new MOPs with enhanced solubility. As a result, the surface-modified MOP 4 was demonstrated as a homogeneous Lewis-acid catalyst. [ABSTRACT FROM AUTHOR]

A NbO-type metal–organic framework, PCN-46, was constructed based on a polyyne-coupled di-isophthalate linker formed in situ. Its lasting porosity was confirmed by N2adsorption isotherm, and its H2, CH4and CO2adsorption capacity was examined at 77 K and 298 K over a wide pressure range (0–110 bar). [ABSTRACT FROM AUTHOR]

Solid-gas reactions and in situ powder X-ray diffraction investigations of trinuclear silver complexes {[3,4,5-(CF 3 ) 3 Pz]Ag} 3 and {[4-Br-3,5-(CF 3 ) 2 Pz]Ag} 3 supported by highly fluorinated pyrazolates reveal that they undergo intricate ethylene-triggered structural transformations in the solid-state producing dinuclear silver-ethylene adducts. Despite the complexity, the chemistry is reversible producing precursor trimers with the loss of ethylene. Less reactive {[3,5-(CF 3 ) 2 Pz]Ag} 3 under ethylene pressure and low-temperature conditions stops at an unusual silver-ethylene complex in the trinuclear state, which could serve as a model for intermediates likely present in more common trimer-dimer reorganizations described above. Complete structural data of three novel silver-ethylene complexes are presented together with a thorough computational analysis of the mechanism., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The activation and CO2 capture properties of a microporous metal-organic framework with elastic single-molecule traps were systematically investigated. This material shows a unique low-energy gas-purge activation capability, high CO2 adsorption selectivities over various gases and optimized working capacities per energy of 2.9 mmol kJ(-1) at 128 °C.

A multi-functional MOF was constructed from Cu paddlewheel motifs and a judiciously designed novel ligand bearing carboxylate, pyridine, and amide groups. exhibits selective adsorption of CO(2) over CH(4) and excellent catalytic activity in a tandem one-pot deacetalization-Knoevenagel condensation reaction as a cooperative catalyst.

Two common radical anion reductants, potassium benzophenone ketyl (K(Ph(2)CO)) and potassium naphthalenide (K(2)(C(10)H(8))(2)(THF)), have been isolated and characterized for the first time in solvent-free form or with low solvent content, allowing their use as pure solid reactants in preparative redox chemistry in accurate stoichiometric amounts.

Hexaferrocenylbenzene has been synthesized by six-fold Negishi type ferrocenylation of hexabromo- or hexaiodobenzene.