Syntheses, structures, and electrochemistry of a dinuclear compound and a mononuclear-mononuclear cocrystalline compound of uranyl(IV)

Autor(en)

Michel Fleck, Susanta Hazra, Samit Majumder, Sasankasekhar Mohanta

Abstrakt

Syntheses, structures, and electrochemistry of a dialkoxo-bridged diuranyl(VI) compound [(UO2)2(L1)2(dimethylformamide)2] (1) and a mononuclear-mononuclear cocrystalline compound [(UO2)(L2)(H2O)(H2O)]·[(UO2)(L2)(H2O)] (2) derived from Schiff base ligands are reported (H2L1 = Schiff base ligand obtained on condensation of 3-ethoxysalicylaldehyde with 2-aminoethanol; H2L2 = N,N -o -phenylenebis(3-ethoxysalicylaldimine)). The compounds 1 and 2 crystallize in the space groups P 21/c and P 1, respectively. Compound 1 is a dialkoxo-bridged dinuclear compound of uranium(VI) containing two deprotonated ligands, [L]2-, two dimethylformamide (dmf) molecules and two UO22+ centers. Three C-H···O type hydrogen bonds involving one uranyl oxygen, two dmf hydrogens, and the imine hydrogen link the dinuclear units into a two-dimensional network. Compound 2 is a cocrystal of two mononuclear units, [(UO2)(L2)(H2O)(H2O)] (unit 1) and [(UO2)(L2)(H2O)] (unit 2). In unit 1, the non-coordinated water molecule forms hydrogen bonds with oxygens of phenoxo, ethoxy, and coordinated water molecules resulting in the formation of an inclusion product. The overall supramolecular structure of compound 2 is one-dimensional and consists of interlinked self-assembled dimeric unit of unit 1 and unit 2. Cyclic voltammetric measurements reveal that the uranium(VI) center in [(UO2)2(L1)2(dimethylformamide)2] (1) is reduced quasireversibly at E1/2 = -773 mV with EP = 121 mV, while the metal center in [(UO2)(L2)(H2O)(H2O)]·[(UO2)(L2)(H2O)] (2) is reduced reversibly with E1/2 = -765 mV with EP = 68 mV.

Organisation(en)

Institut für Mineralogie und Kristallographie

Externe Organisation(en)

University of Calcutta

Journal

Crystal Research and Technology: journal of experimental and industrial crystallography

Band

43

Seiten

1220-1229

Anzahl der Seiten

10

ISSN

0232-1300

Publikationsdatum

2008

Peer-reviewed

Ja

ÖFOS 2012

105113 Kristallographie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/3e33b6c5-5f2f-4494-9c9b-c77747d8d34b