CONFORMATION OF DIETHYLGLYOXIME IN URANYL COMPLEXES
1523
40°C (the molar ratio U : C6H12N2O2 was 1 : 2). The
resulting yellow precipitate was filtered off, washed
with water and several times with alcohol and ether,
and dried on the filter in the air flow. Yield, 2.7 g
(80%).
For [UO2(C6H10N2O2)(H2O)2] ⋅ 2H2O anal. calcd.
(%): UO2, 55.76; N, 5.78; C, 14.88.
Found (%): UO2, 55.26, 55.38; N, 5.25, 5.46; C,
14.37, 14.29.
Uranyl bis(dimethylsulfoxide)diethylglyoximate (III).
A suspension of complex II (1 g) in DMSO (10 mL)
was stirred under heating for 6 h. The precipitate of
dark yellow color was filtered off, washed with water,
and dried on the filter in an air flow. Yield, 0.85 g (72%).
For [UO2(C6H10N2O2)(H2O)2] ⋅ 2H2O anal. calcd.
(%): UO2, 47.50; N, 4.93; C, 21.13.
Found (%): UO2, 47.18, 47.21; N, 5.08, 5.16; C,
20.87, 20.79.
Guanidinium dioxalato-μ-diethylglyoximato-μ-car-
bonatodiuranilate monohydrate (IV). Uranyl nitrate
hexahydrate (2 g) and guanidinium oxalate (1 g) were
stirred on heating in 40 mL of water. Complex I (0.3 g)
in ethanol (20 mL) was added to the resulting light yel-
low hot suspension, and solid guanidinium carbonate
(0.72 g) was added slowly (with stirring and heating)
until the precipitate completely dissolved (molar ratio
Elemental analysis for carbon, hydrogen, and nitro-
gen was carried out on a Carlo Erba CHN analyzer at
the Shared Facility Center of the Kurnakov Institute.
IR spectra of the samples were recorded on a
Lumex Infralum FT-02 Fourier-transform spectro-
photometer in the range of 4000−400 cm−1 at a reso-
lution of 1 cm–1. Samples were prepared as Nujol
(Aldrich) mulls.
X-ray diffraction. The sets of diffraction reflections
for the structure of I were collected on an Enraf-
Nonius CAD4 four-circle automatic diffractometer at
ambient temperature (CuKα radiation, λ = 1.54178 Å,
graphite monochromator); those for complex IV were
collected on a SMART APEX II automatic diffrac-
tometer at 150 K (MoKα-radiation, λ = 0.71073 Å,
graphite monochromator) at the Shared Facility Cen-
ter of the Kurnakov Institute. The data were corrected
for absorption based on equivalent reflections.
The structures were solved by direct methods and
refined by the full-matrix least-squares method for all
non-hydrogen atoms in the anisotropic approxima-
tion. All hydrogen atoms in both structures, except of
H(1) in I as well as H(1) and H(2) in IV, were calcu-
lated geometrically and refined within the riding
model. The hydroxyl hydrogen atom in I and hydro-
gen atoms of the water molecule in IV were located
from difference electron density syntheses and refined
using the least-squares method in the isotropic
approximation. The structures were solved using the
SHELXS and SHELXL software [6].
2−
2−
U :
C H N O :
= 1 : 1.2 : 1 : 1.0). The
CO3
C2O4 :
resulting red 6solution 2was filtered off and allowed to
crystallize in air. After 2−3 h, orange platelike crystals
were filtered and dried on the filter in an air flow.
Yield, 1.8 g (76%).
12
2
Selected crystal data, details of data collection, and
characteristics of structure refinement for complexes I
and IV are listed in Table 1, bond lengths and bond
angles are presented in Table 2, and parameters of
hydrogen bonds are shown in Table 3. The crystallo-
graphic data were deposited with the Cambridge
Structural Database, CCDC nos. 1485431 (I) and
1485432 (IV).
For (CN3H6)4[(UO2)2(C6H10N2O2)(CO3)(C2O4)2] ⋅
H2O anal. calcd. (%): UO2, 45.90; N, 16.67; C, 15.31.
Found (%): UO2, 45.89, 46.01; N, 16.89, 16.27; C,
16.10, 16.05.
Guanidinium ethylenediammonium dioxalato-μ-
diethylglyoximato-μ-carbonatodiuranylate trihydrate
(V). Uranyl nitrate hexahydrate (2 g) and ethylene-
diammonium oxalate (0.72 g) were stirred with heating
in 60 mL of water. Complex I (0.3 g) in ethanol (20 mL)
was added to the light yellow hot suspension, and solid
guanidinium carbonate (0.72 g) was added slowly
(with stirring and heating) until the precipitate com-
2−
RESULTS AND DISCUSSION
Centrosymmetric diethylglyoxime molecules in
the structure of I are in the trans-conformation. The
interatomic distances and angles (Table 2) in I almost
coincide with those in the structures of dimethylglyox-
ime [1] and methylethylglioxime [2].
In the structure of I, diethylglyoxime molecules are
joined by O–H···N intermolecular hydrogen bonds
(2.80 Å) to form a chain along the a axis (Fig. 1).
Similar fragments with hydrogen bonds are typical
of other non-alicyclic α-dioximes [1, 2]; therefore we
can assume that the presence of double hydrogen
bonds O–H···N is crucial for the flat trans-conforma-
tion of molecules of these compounds.
The main fragment of molecule I, with the excep-
tion of methyl groups and hydrogen atoms, is planar
(Fig. 2). Methyl groups are in trans-position relative to
pletely dissolved (molar ratio U :
C H N O :
6 12 2 2
C2O4 :
2− = 1 : 1.2 : 1 : 1.0). The resulting red solution was
CO3
filtered off and allowed to crystallize in air. After 2−3 h,
the orange plate-like crystals were filtered off and
dried on the filter in an air flow. Yield, 1.6 g (69%).
For
(CN3H6)2(C2H10N2)[(UO2)2(C6H10N2O2)(CO3)(C2O4)2] ⋅
3H2O anal. calcd. (%): UO2, 46.78; N, 12.13; C, 15.60.
Found (%): UO2, 46.30, 46.30; N, 12.54, 12.67; C,
16.23, 16.19.
RUSSIAN JOURNAL OF INORGANIC CHEMISTRY Vol. 61 No. 12 2016