58394-95-9Relevant academic research and scientific papers
Heterometallic hexanuclear isobutyrate clusters based on di- and tripodal alcohols
Malaestean, Iurii L.,Speldrich, Manfred,Ellern, Arkady,Baca, Svetlana G.,K?gerler, Paul
, p. 1990 - 1997 (2010)
Four hexanuclear coordination clusters containing {M4II M2III} cores of edge-sharing coordination octahedra exemplify how mixed-spin derivatives of a homonuclear parent structure, [Mn4II Mn2III L8(N-O)4], can be realized by a ligand 'shrink-wrapping' approach, resulting in [Mn2II Co2II Mn2III L8(N-O)4]- and [Co4II Fe2III L8(N-O)4]-type clusters (L = isobutyrate, N-O = methyldiethanolamine, n-butyldiethanolamine, or triethanolamine). The resulting core structures are either virtually isostructural to the parent structure or differ in the placement of the peripheral metal ions, depending on the mix of structure-directing carboxylate and alkoxyamine ligands with large, flexible alkyl chains. Whereas the {Mn4II Mn2III} and {Co4II Fe2III} complexes show dominant antiferromagnetic exchange, ferrimagnetic coupling features are exhibited by two {Mn2II Co2II Mn2III} clusters.
{CoII/III5} horseshoe and {NiII4} lacunary cubane coordination clusters: The isobutyrate/N-butyldiethanolamine reaction system
Schmitz, Sebastian,Monakhov, Kirill Yu.,Van Leusen, Jan,Izarova, Natalya V.,He?, Volkmar,K?gerler, Paul
, p. 100664 - 100669 (2016)
The polynuclear coordination compounds [CoII3CoIII2 (Hbda)2(bda)2(ib)6]·2MeCN (1) and [NiII4 (Hbda)3(ib)5(MeCN)] (2) (H2bda = N-butyldiethanolamine, ib = isobutyrate) are prepared under aerobic conditions using an identical synthetic protocol that solely differs in the employed transition metal (CoIIvs. NiII). Whereas compound 1 displays a mixed-valent, pentanuclear, horseshoe-shaped structure with alternating Co(ii) and Co(iii) ions, compound 2 presents a tetrahedrally-shaped Ni(ii) structural motif where four nickel centers are bridged by three O atoms to afford a lacunary Ni4O3 cubane, a motif hitherto only observed as a substructure of higher-nuclearity coordination clusters and polyoxometalates. Both compounds are thermally surprisingly stable (>130 °C). 1 exhibits weak antiferromagnetic exchange interactions; 2 shows a ferromagnetic coupled triangle of three Ni centers interacting antiferromagnetically with a single Ni apex.
Structural insights into the usage of carboxylate ions as molecular pins
Swiatkowski, Marcin,Kruszynski, Rafal
, p. 265 - 277 (2017/08/10)
Two series of new isostructural coordination compounds containing cobalt, nickel, copper butyrates (butyr) or isobutyrates (ibutyr) and 1,10-phenanthroline (phen), of general formulas [M(phen)3]2+·2(butyr?)·11H2O and [M(phen)3]2+·2(ibutyr?)·14H2O, were synthesized in water solutions and characterized by X-ray crystallography, IR, UV–Vis and fluorescence spectroscopy, elemental and thermal analysis. The carboxylate anions are located in an outer coordination sphere, which is a unique phenomenon in case of ibutyr coordination compounds. The studied compounds exhibit layered packing in crystal net. The “aqueous layers” consist of water molecules and carboxylate groups of carboxylate anions, assembled via hydrogen bonds to the two dimensional supramolecular networks containing multiple different cyclic motifs. Coordination units together with aliphatic ends of carboxylate anions form the “coordination moieties layers”, which are internally connected via π?π and C–H?π intermolecular interactions. The carboxylate anions function as supramolecular linkers between these layers and allow pinning them together. The spectroscopic and thermal properties have been discussed and correlated with molecular structures of the studied compounds. Due to placement of carboxylate anions out of coordination moieties, the presented compounds can be ideal standards in spectroscopic determinations of coordination type of butyr and ibutyr ions in coordination compounds. The thermal analyses of the studied compounds revealed the possibility of formation of dihydrate forms, and such dihydrated compounds cannot be produced in direct synthesis performed in aqueous media. In properly set environment the studied compounds can be thermally converted to micro- and nanoparticles of respective metal oxides.
