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Synthesis and Purification of Iodoaziridines Involving Quantitative Selection of the Optimal Stationary Phase for Chromatography
Published on: May 16, 2014
Poly[di-μ-aqua-μ(4)-(pyrazine-2,5-dicarboxyl-ato)-dilithium(I)]
Wojciech Starosta1, Janusz Leciejewicz
1Institute of Nuclear Chemistry and Technology, ul.Dorodna 16, 03-195 Warszawa, Poland.
Abstract:
In the title coordination polymer, [Li(2)(C(6)H(2)N(2)O(2))(H(2)O)(2)](n) the pyrazine-2,5-dicarboxyl-ate dianionic ligand bridges two symmetry-independent Li(+) ions using both its N,O-chelating sites. The carboxyl-ate O atom of one of them also bridges to another Li(+) ion, while the second O atom of this group is bonded to another Li(+) ion. Two symmetry-independent water O atoms participate also in the bridging system, which gives rise to a polymeric three-dimensional framework. Both Li(+) ions show distorted trigonal-bipyramidal LiNO(4) coordination geometries, with the N atom in an axial site in both cases. The packing is consolidated by O-H⋯O hydrogen bonds, which occur between water mol-ecules as donors and carboxyl-ate O atoms as acceptors.
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