3 research outputs found
Liberalization Of Account Of Operations With Capital And Violation Of Financial Stability
У статті досліджено вплив процесів фінансової лібералізації на стан макроекономічної та фінансової стійкості, альтернативні позиції щодо використання інструментів контролю над капіталом з метою нейтралізації проциклічного впливу міжнародних потоків капіталу.In the article influence of processes of financial liberalization is investigational on the state of macroeconomic and financial firmness, alternative positions in relation to the use of control instruments above a capital with the aim of neutralization of проциклічного influence of international streams of capital
How Amidoximate Binds the Uranyl Cation
This study identifies how the amidoximate anion, AO,
interacts
with the uranyl cation, UO<sub>2</sub><sup>2+</sup>. Density functional
theory calculations have been used to evaluate possible binding motifs
in a series of [UO<sub>2</sub>(AO)<sub><i>x</i></sub>(OH<sub>2</sub>)<sub><i>y</i></sub>]<sup>2–<i>x</i></sup> (<i>x</i> = 1–3) complexes. These motifs
include monodentate binding to either the oxygen or the nitrogen atom
of the oxime group, bidentate chelation involving the oxime oxygen
atom and the amide nitrogen atom, and η<sup>2</sup> binding
with the N–O bond. The theoretical results establish the η<sup>2</sup> motif to be the most stable form. This prediction is confirmed
by single-crystal X-ray diffraction of UO<sub>2</sub><sup>2+</sup> complexes with acetamidoxime and benzamidoxime anions
Influence of Charge on Anion Receptivity in Amide-Based Macrocycles
Binding and structural aspects of anions with tetraamido/diquaternized
diamino macrocyclic receptors containing <i>m</i>-xylyl,
pyridine, and thiophene spacers are reported. <sup>1</sup>H NMR studies
indicate that the quaternized receptors display higher affinities
for anions compared to corresponding neutral macrocycles. The macrocycles
containing pyridine spacers consistently display higher affinity for
a given anion compared to those with either <i>m</i>-xylyl
or thiophene spacers. The <i>m</i>-xylyl- and pyridine-containing
receptors exhibit high selectivity for H<sub>2</sub>PO<sub>4</sub><sup>–</sup> in DMSO-<i>d</i><sub><i></i>6</sub> with association constants, <i>K</i><sub>a</sub> = 1.09 × 10<sup>4</sup> and >10<sup>5</sup> M<sup>–1</sup>, respectively, and moderate selectivity for Cl<sup>–</sup> with <i>K</i><sub>a</sub> = 1.70 × 10<sup>3</sup> and 5.62 × 10<sup>4</sup> M<sup>–1</sup>, respectively.
Crystallographic studies for the Cl<sup>–</sup> and HSO<sub>4</sub><sup>–</sup> complexes indicate that the <i>m</i>-xylyl-containing ligand is relatively elliptical in shape, with
the two charges at ends of the major axis of the ellipse. The anions
are hydrogen bonded with the macrocycle but are outside the ligand
cavity. In the solid state, an unusual low-barrier hydrogen bond (LBHB)
was discovered between two of the macrocycle’s carbonyl oxygen
atoms in the HSO<sub>4</sub><sup>–</sup> complex. The pyridine-containing
macrocycle folds so that the two pyridine units are face-to-face.
The two I<sup>–</sup> ions are chelated to the two amides adjacent
to a given pyridine. In the structure of the thiophene containing
macrocycle with two BPh<sub>4</sub><sup>–</sup> counterions,
virtually no interaction was observed crystallographically between
the macrocycle and the bulky anions