Synthesis and crystal structures of two new uranyl coordination compounds obtained in aqueous solutions of 1-butyl-2,3-dimethylimidazolium chloride
Abstract
<p>Two new uranyl coordination compounds, [C<sub>9</sub>H<sub>17</sub>N<sub>2</sub>]<sub>3</sub>[(UO<sub>2</sub>)<sub>2</sub>(CrO<sub>4</sub>)<sub>2</sub>Cl<sub>2</sub>(H<sub>2</sub>O)<sub>2</sub>]Cl·5H<sub>2</sub>O (<b>1</b>) and (C<sub>9</sub>H<sub>17</sub>N<sub>2</sub>)[(UO<sub>2</sub>)(C<sub>2</sub>O<sub>4</sub>)Cl] (<b>2</b>), have been synthesized by adding potassium dichromate (K<sub>2</sub>Cr<sub>2</sub>O<sub>7</sub>) or oxalic acid dihydrate (H<sub>2</sub>C<sub>2</sub>O<sub>4</sub>·2H<sub>2</sub>O) solution into an aqueous solution of uranyl nitrate and 1-butyl-2,3-dimethylimidazolium chloride [Bmmim]Cl. [Bmmim]Cl provides the charge balance and Cl ions that coordinate with uranyl ions. The fundamental building units of <b>1</b> and <b>2</b> are UO<sub>6</sub>Cl pentagonal bipyramidal structures. Compound <b>1</b> exhibits a graphene-like structure with a system molar ratio of 1:1 for U:Cr and crystallizes in the orthorhombic space group Pbca, with <i>a</i> = 25.644(3) Å, <i>b</i> = 12.996(14) Å and <i>c</i> = 29.198(4) Å. 16-Membered rings are formed by CrO<sub>4</sub><sup>2−</sup> and UO<sub>2</sub><sup>2+</sup> in the crystal structure of <b>1</b>. Compound <b>2</b> crystallizes in monoclinic space group P2<sub>1</sub>/n, with <i>a</i> = 10.759(3) Å, <i>b</i> = 11.395(3) Å, <i>c</i> = 14.149(4) Å, <i>β</i> = 102.962(9)° and shows one-dimensional (1D) serrated chains. Within the crystal structures of <b>1</b> and <b>2</b>, C–H<sub>[Bmmim]Cl</sub>⋯O hydrogen bonds are identified. O–H<sub>water</sub>⋯Cl hydrogen bonds are also detected in the crystal structure for <b>1</b>.</pSimilar works
Full text
