Influence of the synthetic conditions on the structural diversity of extended manganese-oxalato-1,2-bis(4-pyridyl)ethylene systems.

We report herein the synthesis and physicochemical characterization of eight new manganese-oxalato compounds with 1,2-bis(4-pyridyl)ethylene (bpe): {(Hbpe)(2)[Mn(2)(μ-ox)(3)]·∼0.8(C(2)H(5)OH)·∼0.4(H(2)O)}(n) (1), {[Mn(μ-ox)(μ-bpe)]·xH(2)O}(n) (2), [Mn(2)(μ-ox)(2)(μ-bpe)(bpe)(2)](n) (3), [Mn(μ-ox)(μ-bpe)](n) (4a and 4b), and {[Mn(4)(μ-ox)(3)(μ-bpe)(4)(H(2)O)(4)]·(X)(2)·mY}(n) with X = NO(3)(-) (5a), Br(-) (5b), and ClO(4)(-) (5c) and Y = solvation molecules.

Rational design of 1-D metal-organic frameworks based on the novel pyrimidine-4,6-dicarboxylate ligand. New insights into pyrimidine through magnetic interaction.

Single crystal X-ray analysis of compounds H2pmdc.2H2O (1), KHpmdc (2), and K2pmdc (3) shows that the pyrimidine-4,6-dicarboxylate (pmdc) dianion presents an almost planar geometry which confers a potential capability to act as a bis-bidentate bridging ligand, and therefore, to construct 1-D metal complexes. Based on this assumption, we have designed the first six transition metal complexes based on this ligand of formula {[M(micro-pmdc)(H2O)2].

Molecular recognition of adeninium cations on anionic metal-oxalato frameworks: an experimental and theoretical analysis.

Reactions of adenine with water-soluble oxalato complexes at acidic pH give the compounds (1H,9H-ade)2[Cu(ox)2(H2O)] (1) [H2ade=adeninium cation (1+), ox=oxalato ligand (2-)] and (3H,7H-ade)2[M(ox)2(H2O)2].2H2O [M(II)=Co (2), Zn (3)]. The X-ray single crystal analyses show that the supramolecular architecture of all compounds is built up of anionic sheets of metal-oxalato-water complexes and ribbons of cationic nucleobases among them to afford lamellar inorganic-organic hybrid materials.

Supramolecular architectures and magnetic properties of coordination polymers based on pyrazinedicarboxylato ligands showing embedded water clusters.

The synthesis, crystal structure, and magnetic behavior of nine transition-metal complexes based on pyrazine-2,5-dicarboxylato (pz25dc) and pyrazine-2,3-dicarboxylato (pz23dc) ligands are reported. The pz25dc ligand displays a bis-bidentate coordination mode, with the carboxylate groups almost coplanar with the pyrazine ring, to afford polymeric 1-D chains [Mn(1), Fe(2), Zn(3), and Cu(4 and 5)] and discrete dimeric entities [Mn(6)] when the 1,10-phenanthroline (phen) blocking ligand is used to avoid further polymerization. The nonplanar pz23dc ligand chelates to a unique copper center, while it bridges another one or two metal centers via the remaining carboxylate group, leading to 1-D polymeric chains (7), ladder chains (8), and sheets (9).

Supramolecular architectures assembled by the interaction of purine nucleobases with metal-oxalato frameworks. Non-covalent stabilization of the 7H-adenine tautomer in the solid-state.

The synthesis, crystal structure and variable-temperature magnetic measurements of the compounds [Mn(mu-ox)(H2O)(7H-pur-kappaN9)]n (1), {[Mn(mu-ox)(H2O)2].(7H-ade).(H2O)}n (2) and {[Cu(mu-ox)(H2O)(7H-ade-kappaN9)][Cu(mu-ox)(mu-H2O)(7H-ade-kappaN9)].

Scanning probe microscopy characterization of single chains based on a one-dimensional oxalato-bridged manganese(II) complex with 4-aminotriazole.

The compound [Mn(mu-ox)(4atr)2]n (1) (ox = oxalato and 4atr = 4-amine-1,2,4-triazole) has been synthesized and characterized by FT-IR spectroscopy, thermal analysis, variable-temperature magnetic measurements, and X-ray single-crystal diffraction methods. The crystal structure of compound 1 consists of one-dimensional linear chains in which trans-[Mn(4atr)2]2+ units are sequentially bridged by centrosymmetric bis-bidentate oxalato ligands. Cryomagnetic measurements show an overall antiferromagnetic behavior of the compound.

One-dimensional oxalato-bridged Cu(II), Co(II), and Zn(II) complexes with purine and adenine as terminal ligands.

The reaction of nucleobases (adenine or purine) with a metallic salt in the presence of potassium oxalate in an aqueous solution yields one-dimensional complexes of formulas [M(mu-ox)(H(2)O)(pur)](n) (pur = purine, ox = oxalato ligand (2-); M = Cu(II) [1], Co(II) [2], and Zn(II) [3]), [Co(mu-ox)(H(2)O)(pur)(0.76)(ade)(0.24)](n)(4) and ([M(mu-ox)(H(2)O)(ade)].

An unusual 3D coordination polymer based on bridging interactions of the nucleobase adenine.

The first 3D coordination polymer containing a nucleobase as a bridging ligand, [[Cu2(mu-ade)4(H2O)2][Cu(ox)(H2O)]2 x approximately 14H2O]n (1), has been synthesized by reaction of adenine (Hade) with a basic solution of K2[Cu(ox)2] x 2H2O (ox = oxalato dianion). Compound 1 crystallizes in the trigonal space group R3 with a = b = 31.350(1) angstroms, c = 14.