Metal complexes as potential ligands: The deprotonation of aminephenolate metal complexes

Syntheses, Structures, and Corrosion Inhibition of Various Alkali Metal Carboxylate Complexes

Complexes of the alkali metals Li-Cs with 3-thiophenecarboxylate (3tpc), 2-methyl-3-furoate (2m3fur), 3-furoate (3fur), 4-hydroxycinnamate (4hocin), and 4-hydroxybenzoate (4hob) ions were prepared via neutralisation reactions, and the structures of [Li₂(3tpc)₂]_n (1Li); [K₂(3tpc)₂]_n (1K); [Rb(3tpc)(H₂O)]_n (1Rb); [Cs{H(3tpc)₂}]_n (1Cs); [Li₂(2m3fur)₂(H₂O)₃] (2Li); [K₂(2m3fur)₂(H₂O)]_n (2K); [Li(3fur)]_n(3Li); [K(4hocin](H₂O)₃]_n (4K); [Rb{H(4hocin)₂}]_n.nH₂O (4Rb); [Cs(4hocin)(H₂O)]_n (4Cs); [Li(4hob)]_n (5Li); [K(4hob)(H₂O)₃]_n (5K); [Rb(4hob)(H₂O)]_n (5Rb); and [Cs(4hob)(H₂O)]_n (5Cs) were determined via X-ray crystallography. Bulk products were also characterised via XPD, IR, and TGA measurements. No sodium derivatives could be obtained as crystallographically suitable single crystals. All were obtained as coordination polymers with a wide variety of carboxylate-binding modes, except for dinuclear 2Li. Under conditions that normally gave coordinated carboxylate ions, the ligation of hydrogen dicarboxylate ions was observed in 1Cs and 4Rb, with short H-bonds and short O…O distances associated with the acidic hydrogen. The alkali-metal carboxylates showed corrosion inhibitor properties inferior to those of the corresponding rare-earth carboxylates.

Potassium induced stitching of a flexible tripodal ligand into a bi-metallic two-dimensional coordination polymer for photo-degradation of organic dyes

A novel strategy for the stitching of a flexible tripodal ligand into a bimetallic two-dimensional coordination polymer was developed for photo-degradation of dyes.

Tetradentate Schiff base beryllium complexes

The structure of (BeSalen)₂ is reported. The incompatibility of the geometry of beryllium with the inflexibility of the Salen gives rise to a rare dimeric motif.

Alkali metal complexes of 6-methyl-2-pyridone: simple formulae, but not so simple structures

Reaction of 6-methyl-2-pyridone (Hmhp) with Na or K metal, or with Rb or Cs 2-ethylhexoxide, in an appropriate single or mixed solvent, yields a series of solvated polymeric complexes with the empirical formulae M(mhp)(H2O)2 [(1), M = Na; (2), M = K], M(mhp)(H2O) [(3), M = Rb; (4), M = Cs] and Cs(mhp)(ROH) [(5), R = Me; (6), R = Et]. All of the products have been crystallographically characterized and show sheet polymeric structures, except for a double-chain structure for (2). In all of the structures, mhp(-) and solvent molecules function as bridging ligands; two metal ions are bridged (μ2) by each solvent molecule in (1), (5) and (6), while (2) contains both μ2 and μ3 triple bridges, and (3) and (4) display highly unusual μ4 quadruple bridging of metal ions by water molecules. The pyridonate O atom bridges two or three metal ions in each case. Nitrogen is also involved in coordination to the heavier metals; it bonds to a single ion in (3) and (4), but has an almost unprecedented bridging role in (5) and (6). As a result of the extensive bridging by ligands, coordination numbers between 6 and 8 are achieved for the metal ions. In each structure, all solvent OH groups form hydrogen bonds to pyridonate O and, in some cases, N atoms. With one exception, these are the first reported pyridonate complexes of the alkali metals Na-Cs that do not also include transition metals.