A three-dimensional Zn^II coordination network based on 5,5′-methylenebis(2,4,6-trimethylisophthalic acid) and 2,7-bis(1H-imidazol-1-yl)fluorene: synthesis, structure and luminescence properties

Abstract

Keywords: two-dimensional coordination polymer; zinc(II); 5,5 0 -methylenebis(2,4,6-trimethylisophthalic acid; 2,7-bis(1H-imidazol-1yl)fluorene; hydrogen bonding; fluorescence properties; crystal structure; supramolecular. CCDC reference: 1875032Supporting information: this article has supporting information at journals.iucr.org/c A three-dimensional Zn II coordination network based on 5,5 0 0 0 -methylenebis(2,4,6-trimethylisophthalic acid) and 2,7-bis(1H-imidazol-1-yl)fluorene: synthesis, structure and luminescence properties In recent years, coordination polymers constructed from multidentate carboxylate ligands and N-containing ligands have attracted much attention since these ligands can adopt a rich variety of coordination modes which can lead to crystalline products with intriguing structures and interesting properties. A new coordination polymer, namely poly[[diaqua [-2,7-.5H 2 O} n , 1, was prepared by the self-assembly of Zn(NO 3 ) 2 Á6H 2 O with 5,5 0 -methylenebis(2,4,6trimethylisophthalic acid) (H 4 BTMIPA) and 2,7-bis(1H-imidazol-1-yl)fluorene (BIF) under solvothermal conditions. The structure of 1 was determined by elemental analysis, single-crystal X-ray crystallography, powder X-ray diffraction, IR spectroscopy and thermogravimetric analysis. Each Zn II ion is sixcoordinated by two O atoms from two H 2 BTMIPA 2À ligands, by two N atoms from two BIF ligands and by two water molecules, forming a distorted octahedral ZnN 2 O 4 coordination geometry. Adjacent Zn II ions are linked by H 2 BTMIPA 2À ligands and BIF ligands, leading to the formation of a twodimensional (2D) (4,4)-sql network, and intermolecular hydrogen-bonding interactions connect the 2D layer structure into the three-dimensional (3D) supramolecular structure. Each 2D layer contains two kinds of helices with the same direction, which are opposite in adjacent layers. The luminescence properties of complex 1 in the solid state have also been investigated.

Production of functional spherical particles with porous hollow structures in water via oiling-out directional agglomeration

“…(I) The spherical external shape improves the flowability and tabletability of the drug powder, enabling direct compression to be achieved with remarkable economic value. 10,11 (II) The hollow internal structure further enhances the compression properties during tableting. 12,13 (III) The porous hollow structure has a large surface area and a low bulk density, resulting in higher dissolution rates and smaller aerodynamic diameters (important for deep lung delivery).…”