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The crystal structure of the title compound, [Ni(C8H20N4)(NO3)]NO3, at room temperature, has monoclinic (P21/n) symmetry. The structure displays inter-molecular hydrogen bonding. The nickel displays a distorted bipyramidal geometry with the symmetric bidentate bonded nitrate occupying an equatorial site. The 1,4,7,10-tetraazacyclododecane (cyclen) backbone has the [4,8] configuration, with three nitrogen-bound H atoms directed above the plane of the nitrogen atoms towards the offset nickel atom with the fourth nitrogen-bound hydrogen directed below from the plane of the nitrogen atoms. The nitrate anion O atoms are seen to hydrogen bond to the H atoms bound to the N atoms of the ligand. [ABSTRACT FROM AUTHOR]

Fluorination of azopyridine N-donors regulates the formation of either B ← N coordination adducts or a co-crystal with phenylboronic acid catechol ester. Specifically, the formation of B ← N adducts is promoted by azopyridines with up to four fluorines, while perfluorination affords a co-crystal via phenyl–perfluoropyridyl [π⋯πF] contacts. Electrostatic potential maps showed supramolecular bonding competition outcomes to be primarily determined by modulation of electron-donating capacity and π surfaces of azopyridine N-donors using fluorination. [ABSTRACT FROM AUTHOR]

An application of multi‐component milling is described to achieve a decolorization by dismantling the orange‐red zwitterionic cocrystal (PDA)∙(APAP) (where PDA = 2,4‐pyridinedicarboxylic acid, APAP = acetaminophen) using n,n′‐BPE (BPE = trans‐1,2‐bis(n‐pyridylethylene and for n = n′ = 3 or 4). Each of n,n′‐BPE forms a colorless hydrogen‐bonded cocrystal with PDA. [ABSTRACT FROM AUTHOR]

Three complexes containing diosmium(I) sawhorse units have been synthesized by reactions of 1,1'-bis(diphenylphosphino)ferrocene (dppf) with [Os2(µ-acetate)2(CO)6], [Os2(µ-acetate)2(CO)4(κ1-dppf)2] (1), [(µ-dppf){Os2(µ-acetate)2(CO)4(κ1-dppf)}2] (2), and [(µ-dppf)3{Os2(µ-acetate)2(CO)4}3] (3). In all three cases, the axial CO ligands of the diosmium starting material were replaced by axial dppf ligands. Both 1 and 2 contain two monodentate dppf ligands. In each molecule of 2, there is also one bidentate dppf ligand that serves as a bridge between two Os2 sawhorse units. Complex 3 has a unique cyclic molecular structure involving three sawhorse units connected by three bidentate bridging dppf ligands with alternating sawhorse and dppf moieties forming a ring. Complexes 2 and 3 were characterized by X-ray crystallography. [ABSTRACT FROM AUTHOR]

We report channel confinement and separation properties of an adaptive supramolecular framework based on an adamantane tecton. Specifically, the framework is self-assembled from a tetraaryl-substituted adamantane tecton (i.e., 1,3,5,7-tetrakis(4-bromophenyl)adamantane) via van der Waals contacts, phenyl embraces and halogen bonds. The adamantane framework displays modular channels that confine aromatic petrochemicals and chloroform, and enables separation of toluene from benzene via crystallization. [ABSTRACT FROM AUTHOR]

The development of reticular chemistry has enabled the construction of a large array of metal–organic frameworks (MOFs) with diverse net topologies and functions. However, dominating this class of materials are those built from discrete/finite secondary building units (SBUs), yet the designed synthesis of frameworks involving infinite rod‐shaped SBUs remain underdeveloped. Here, by virtue of a global linker desymmetrization approach, we successfully targeted a novel Cu‐MOF (Cu‐ASY) incorporating infinite Cu‐carboxylate rod SBUs with its structure determined by micro electron diffraction (MicroED) crystallography. Interestingly, the rod SBU can be simplified as a unique cylindric sphere packing qbe tubule made of [43.62] tiles, which further connect the tritopic linkers to give a newly discovered 3,5‐connected gfc net. Cu‐ASY is a permanent ultramicroporous material featuring 1D channels with highly inert surfaces and shows a preferential adsorption of propane (C3H8) over propene (C3H6). The efficiency of C3H8 selective Cu‐ASY is validated by multicycle breakthrough experiments, giving C3H6 productivity of 2.2 L/kg. Density functional theory (DFT) calculations reveal that C3H8 molecules form multiple C−H⋅⋅⋅π and atypical C−H⋅⋅⋅ H−C van der Waals interactions with the inner nonpolar surfaces. This work therefore highlights the linker desymmetrization as an encouraging and intriguing strategy for achieving unique MOF structures and properties. [ABSTRACT FROM AUTHOR]

Electrocrystallization of ortho-dimethyltetrathiafulvalene (o-DMTTF) in the presence of a nitrite (NO2−) anion affords a 2 : 1 phase, namely (o-DMTTF)2NO2, the first example of an isolated cation radical salt with NO2−. The o-DMTTF molecule organizes into strongly dimerized stacks that adopt a rare chessboard organization, associated with a strongly 1D structure. As a consequence of dimerization, the salt exhibits a semiconducting behavior (σRT = 5 S cm−1, Eact = 0.1 eV). The bent NO2− anion is disordered on the inversion center but does not exhibit any anion-ordering transition. Combined SQUID magnetometry and electron paramagnetic resonance (EPR) experiments demonstrate the appearance of a spin-Peierls transition with TSP = 70 K. The temperature dependence of the spin gap and associated dimerization parameter δ across the spin-Peierls transition have been determined. The low-temperature narrow EPR line observed below TSP is attributable to intrinsic magnetic defects localized on the o-DMTTF molecules themselves. The broadening of the EPR line at higher magnetic fields is associated with the disordered NO2− anions surrounding these magnetic defects, contributing to the inhomogeneity of their g factor. [ABSTRACT FROM AUTHOR]

Metal-Organic Frameworks (MOFs) are a class of crystalline materials that, thanks to their large surface area and high porosity, allow them to be used in various areas of knowledge. This diversity of applications is due to the metal ions and the organic binders that compose them, but it is also important to highlight the ability of MOFs to function as hosts for a great variety of molecules of very different sizes and chemical properties. The first existing approaches for incorporating biomolecules in MOFs are discussed: pore encapsulation, surface binding, covalent binding, and in-situ encapsulation. Next, we discuss the obstacles of designing MOFs for effective gene delivery and how to enhance the gene delivery using different strategies. [ABSTRACT FROM AUTHOR]