ABSTRACT
Postsynthetic installation of lanthanide cubanes into a metallosupramolecular framework via a single-crystal-to-single-crystal (SCSC) transformation is presented. Soaking single crystals of K6 [Rh4 Zn4 O(l-cys)12 ] (K6 [1]; l-H2 cys=l-cysteine) in a water/ethanol solution containing Ln(OAc)3 (Ln3+ =lanthanide ion) results in the exchange of K+ by Ln3+ with retention of the single crystallinity, producing Ln2 [1] (2Ln ) and Ln0.33 [Ln4 (OH)4 (OAc)3 (H2 O)7 ][1] (3Ln ) for early and late lanthanides, respectively. While the Ln3+ ions in 2Ln exist as disordered aqua species, those in 3Ln form ordered hydroxide-bridged cubane clusters that connect [1]6- anions in a 3D metal-organic framework through coordination bonds with carboxylate groups. This study shows the utility of an anionic metallosupramolecular framework with carboxylate groups for the creation of a series of metal cubanes that have great potential for various applications, such as magnetic materials and heterogeneous catalysts.
ABSTRACT
The crystal structures of five new transition-metal complexes synthesized using thiazole-2-carboxylic acid (2-Htza), imidazole-2-carboxylic acid (2-H2ima) or 1,3-oxazole-4-carboxylic acid (4-Hoxa), namely diaquabis(thiazole-2-carboxylato-κ2N,O)cobalt(II), [Co(C4H2NO2S)2(H2O)2], 1, diaquabis(thiazole-2-carboxylato-κ2N,O)nickel(II), [Ni(C4H2NO2S)2(H2O)2], 2, diaquabis(thiazole-2-carboxylato-κ2N,O)cadmium(II), [Cd(C4H2NO2S)2(H2O)2], 3, diaquabis(1H-imidazole-2-carboxylato-κ2N3,O)cobalt(II), [Co(C4H2N2O2)2(H2O)2], 4, and diaquabis(1,3-oxazole-4-carboxylato-κ2N,O4)cobalt(II), [Co(C4H2NO3)2(H2O)2], 5, are reported. The influence of the nature of the heteroatom and the position of the carboxyl group in relation to the heteroatom on the self-assembly process are discussed based upon Hirshfeld surface analysis and used to explain the observed differences in the single-crystal structures and the supramolecular frameworks and topologies of complexes 1-5.
ABSTRACT
The linear two-coordinate silver (I) complex [Ag(C4H2NO2S)(C4H3NO2S)] or [Ag(2-Htza)(2-tza)] is reported (2-Htza = 1,3-thia-zole-2-carb-oxy-lic acid). The AgI ion is coordinated by two heterocyclic N atoms from two ligands in a linear configuration, forming a discrete coordination complex. There is an O-Hâ¯O hydrogen bond between 2-tza- and 2tzaH of adjacent complexes. The hydrogen atom is shared between the two oxygen atoms. This inter-action produces a hydrogen-bonded tape parallel to the [110] direction, which is augmented through inter-molecular C-Hâ¯O hydrogen-bonding inter-actions between the bound thia-zole groups. There is a further rather long Agâ¯O inter-action [2.8401â (13)â Å, compared with a mean of 2.54â (11)â Å for 23 structures in the CSD] that assembles these tapes into columns, between which there are C-Hâ¯π inter-actions, leading to the formation of a three-dimensional supra-molecular architecture.
ABSTRACT
The crystal structure of the title compound, [Cu(SO4)(C12H8N2)2]·C2H5OH, arises from the assembly of the neutral complex [Cu(SO4)(C12H8N2)2] and an ethanol solvent mol-ecule. The Cu(II) ion is five-coordinate, surrounded by two pairs of N atoms from two independent N,N'-chelating 1,10-phenanthroline ligands, and one O atom of monodentate sulfate ligand, in a distorted trigonal-bipyramidal fashion. Spatial orientation of the ligands and the assembly in the solid state are stabilized by the C-Hâ¯O hydrogen-bonding inter-actions, established between the O atoms (from the sulfate ligand and the ethanol mol-ecule) and the neighbouring 1,10-phenanthroline mol-ecules. There is also an offset face-to-face π-π stacking between the 1,10-phenanthroline ligands. The ethanol solvent mol-ecule is disordered over two orientations in the ratio 0.663â (10):0.337â (10). The crystal examined was subject to racemic twinning and the refined twin fraction was 0.346â (19).
