Developing a magnetic metal organic framework of copper bearing a mixed azido/butane-1,4-dicarboxylate bridge: magnetic and gas adsorption properties.

A magnetic metal organic framework {[Cu(but-1,4-dc)0.5(N3)(H2O)]·H2O}n (MFUM-1(Cu)) (but-1,4-dc = butane-1,4-dicarboxylate) was synthesized and characterized structurally and magnetically. In MFUM-1(Cu), each CuII ion has a distorted octahedral geometry with an obvious Jahn-Teller distortion, where the coordination environment is composed of mixed EO-azido/aliphatic based carboxylate/H2O threefold bridges. These bridges extend the structure of MFUM-1(Cu) in two dimensions by covalent connectivity and form square-shaped channels. Also, a study was done to determine the effectiveness of sonochemical synthesis for the preparation of nano-sheets of MFUM-1(Cu) and subsequently the influence of particle size on physical properties such as magnetic behavior and thermal stability. The particles were characterized by elemental analyses, infrared spectroscopy (IR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and powder X-ray diffraction (PXRD) analyses. The effects of parameters such as concentration, solvent, and reaction time on the size distribution, morphology, and yield of product were carefully studied. The magnetic properties of MFUM-1(Cu) and corresponding nano-structure were examined which indicated metamagnetism with strong intrachain ferromagnetic coupling versus the weak interchain antiferromagnetic coupling. Finally, the application of MFUM-1(Cu) in the separation of carbon dioxide from nitrogen and also from methane was theoretically investigated. High calculated selectivity of CO2 over N2 and CH4 reveals the potential application of MFUM-1(Cu) in practical systems of gas separation.

Bis(2-amino-6-methyl-pyridinium) trans-diaqua-bis-(pyrazine-2,3-dicarboxyl-ato)cuprate(II) hexa-hydrate.

The title compound, (C(6)H(9)N(2))(2)[Cu(C(6)H(2)N(2)O(4))(2)(H(2)O)(2)]·6H(2)O, was obtained by the reaction of CuCl(2)·2H(2)O with pyrazine-2,3-dicarb-oxy-lic acid (pyzdcH(2)) and 2-amino-6-methyl-pyridine (2a-6mpy) in aqueous solution. The Cu(II) atom is located on an inversion centre and has an overall octa-hedral coordination environment. Two N and two O atoms from (pyzdc)(2-) ligands define the equatorial plane and two water mol-ecules are in axial positions, resulting in a typical tetra-gonally Jahn-Teller-distorted environment. Extensive classical O-H⋯O, O-H⋯N and N-H⋯O and non-classical C-H⋯O hydrogen bonds, as well as π-π stacking inter-actions between aromatic rings of the cations [centroid-centroid distance = 3.58 (9) Å], lead to the formation of a three-dimensional supra-molecular structure.

Bis(2,4,6-triamino-1,3,5-triazin-1-ium) pyrazine-2,3-dicarboxyl-ate tetra-hydrate: a synchrotron radiation study.

The title compound, 2C(3)H(7)N(6) (+)·C(6)H(2)N(2)O(4) (2-)·4H(2)O or (tataH)(2)(pzdc)·4H(2)O, was synthesised by a reaction between pyrazine-2,3-dicarboxylic acid (H(2)pzdc) as a proton donor and 2,4,6-triamino-1,3,5-triazin (tata) as a proton acceptor. In the crystal structure, an extensive series of O-H⋯O, O-H⋯N, N-H⋯O and N-H⋯N hydrogen bonds generates a three-dimensional framework with the hydrogen bonding involving most donor and acceptor centers. π-π stacking inter-actions are also observed between adjacent triazine rings, with centroid-centroid distances of 3.4994 (8) and 3.5922 (7) Å.

Acridinium 2-hy-droxy-benzoate.

In the title compound, C(13)H(10)N(+)·C(7)H(5)O(3) (-) or (acrH)(+)(Hsal)(-), the asymmetric unit contains one acridinium cation and one salicylate anion. The acridinium N atom is protonated and the carb-oxy-lic acid group of salicylic acid is deprotonated. Both moieties are planar, with an r.m.s. deviation of 0.0127 Šfor the acr cation and 0.0235 ° for the sal anion. They are aligned with a dihedral angle of 71.68 (3)° between them. The crystal structure is stabilized by a network of inter-molecular N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds. C-H⋯π inter-actions are also present.