Crystallization of Two 1-D Coordination Polymers Building by 5-Sulfoisophthalic Acid and Lanthanide Ions by Partial Hydrolysis of Collagen

Experimental and theoretical structural investigation of an ionic Nd coordination polymer

Research concerning coordination polymers has been intense due to their significant variability and structural stability. With this in mind, an ionic neodymium coordination polymer was synthesized, composed of an anionic one-dimensional polymer interconnected to a cationic three-dimensional porous polymer, poly[dodecaaquabis(μ-pyridine-4-carbohydrazide-κ2N:O)bis(μ2-4-sulfobenzoato-κ2O:O')bis(μ3-4-sulfobenzoato-κ3O:O':O'')trineodymium(III)] catena-poly[aquabis(μ-pyridine-4-carbohydrazide-κ2N:O)bis(μ2-4-sulfobenzoato-κ2O:O')neodymium(III)] 4.33-hydrate, {[Nd3(C7H4O5S)4(C6H7N3O)2(H2O)12][Nd(C7H4O5S)2(C6H7N3O)2(H2O)]·4.33H2O}n. The ligands used were 4-sulfobenzoate (PSB) and pyridine-4-carbohydrazide, popularly known as isoniazid (INH), an antibiotic drug. The compound crystallizes in the monoclinic space group C2/c, with Z = 4. Solid-state calculations suggest that the crystal structure is mainly stabilized by hydrogen bonds, i.e. O-H...O and N-H...O interactions among the polymers, and by van der Waals interactions involving the organic side chains. This net is tetragonal, 2-nodal 3,4-connected, and can be described as the dmd (sqc 528) type.

Synthesis, crystal structure and topological analysis of a three-dimensional polymeric network based on zinc(II), potassium and 5-sulfobenzene-1,3-dicarboxylate (SIP)

Aromatic polycarboxylate linkers provide structural rigidity and strong interactions among the metal centre and the carboxylate O atoms. A new three-dimensional coordination polymer namely, catena-poly[potassium [tetraaqua(μ-5-sulfobenzene-1,3-dicarboxylato)zinc(II)]], {K[Zn(C₈H₃O₇S)(H₂O)₄]}_n or {K[Zn(SIP)(H₂O)₄]}_n, where SIP is 5-sulfobenzene-1,3-dicarboxylate or 5-sulfoisophthalate, was obtained and characterized by elemental analysis and IR vibrational spectroscopy, and the single-crystal structure was determined by X-ray diffraction analysis. The compound crystallizes in the monoclinic space group P2₁/n with Z = 4. Topological analysis revealed that K-O interactions form a two-dimensional network, which is uninodal 4-connected and can be described with a point symbol (4⁴.6²), and this plane network is classified as sql/Shubnikov. The layers are connected by Zn²⁺ ions coordinated to the SIP linker, forming a three-dimensional network. This net is a trinodal (3,5,6)-connected system with point symbol (3.4⁴.5².6².7³.8³).(3.4⁴.5².6².7).(3.7²).