I. M. Orlova

Uranyl complexes with acetophenone oxime

The interaction of uranyl compounds with acetophenone oxime has been studied. Mixed-ligand uranyl acetophenone oximates have been synthesized. X-ray crystallography shows that, in single crystals of [UO2(C8H8NO)2{(CH3)2SO}2] and [UO2(C8H8NO)(NO3){(CH3)2SO}2], acetophenone oxime is coordinated to uranyl as a bidentate chelating ligand.

Uranyl aquahydroxylaminate complexes

Uranylaqua complexes with N-methyl-, N-ethyl-, N-isopropyl-, and N,N-dimethylhydroxylamines were studied. The structure of [UO2{(CH3)2NO}2(H2O)2] was determined by X-ray crystallography. The N, N -dimethylhydroxylaminate ion is coordinated to uranyl through the nitrogen and oxygen atoms with the formation of a three-membered chelate ring.

Molybdenum(VI) complexes with N-substituted hydroxylamines

New molybdenum(VI) complexes with N-monoalkylsubstituted hydroxylamines have been synthesized and studied. The structure of [MoO2(C2H5NHO)2] and [MoO2(i-C3H7NHO)2], whose distinguishing feature is the bidentate chelate coordination of the ligand to molybdenum with the formation of the three-membered NMoO chelate ring, has been determined by X-ray diffraction.

Coordination modes of α-dioximes in uranyl complexes

Abstractα-Dioximes are well-known analytical reagents that comprise two oxime groups. Such ligands have been widely used in the recovery and separation and in analytical determination of d-transition elements. This survey deals with uranyl complexes with α-dioximes, which constitute a new class of uranium(VI) coordination compounds and are distinguished from the other transition-metal glyoximates by unusual coordination modes of the ligand to the central atom.

Uranyl complexes with ethylmethylglyoxime

Uranyl complexes with ethylmethylglyoxime were studied. The structure of (CN3H6)4[(UO2)2(CO3)(C2O4)2(C5H8N2O2)] · 1.5H2O was determined by X-ray crystallography. The structure of the complex is binuclear with a double carbonate dioximate bridging fragment.

Reactions of coordinated ligands in uranyl hydroxylaminate complexes

The reactions of coordinated ligands in uranyl complexes were studied for the first time. The reaction of uranyl hydroxylaminate complexes with aldehyde and ketones of different structure was shown to result in the formation of corresponding oxime complexes.

Reaction between uranyl dihydroxylaminate and benzaldehyde

Reactions of coordinated ligands in uranyl hydroxylaminate complexes with benzaldehyde were studied. Methods of the synthesis of uranyl complexes containing E and Z isomers of benzaldehydoxime were developed. The structures of [UO2((E)-C7H6NO)2{(CH3)2SO}2] and [UO2((Z)-C7H6NO)2{(CH3)2SO}2] were determined by X-ray diffraction.

Uranyl complexes with methyl derivatives of alicyclic dioximes

A reaction of uranyl dioxalate complexes with methyl derivatives of alicyclic α-dioximes, 3-methyl-1,2-cyclohexanedione dioxime and 3-methyl-1,2-cyclopentanedione dioxime, was studied. The structure of (CN3H6)4[(UO2)2(C6H8N2O2)(CO3)(C2O4)2] · (C6H10N2O2) · 2H2O and NH4(CN3H6)3[(UO2)2(C7H10N2O2)(CO3)(C2O4)2] · 2H2O based on binuclear complex anions with carbonate-dioximate fragment was studied by X-ray diffraction.

Uranyl complexes with 1,2-cycloheptanedione dioxime

Uranyl compounds with 1,2-cycloheptanedione dioxime (heptoxime) have been studied. Partial isomerization of the ligand takes place upon the formation of aqua complexes. The coordination modes of heptoxime in uranyl complexes were established by X-ray crystallography on [(UO2)2(C7H10N2O2)2{(CH3)2SO}3] single crystals: cis-(E,E)tetradentate chelating bridging and cis-(E,Z)pentadentate chelating bridging.

“Forced” coordination modes of 1,2-cyclohexanedione dioxime in uranyl complexes

Unusual coordination modes of 1,2-cyclohexane dionedioxime in uranyl complexes, i.e., tridentate chelating/bridging and (E, Z)-pentadentate chelating/bridging ones, were established by X-ray crystallography of single crystals of (CN3H6)3[(UO2)2(C6H9N2O2)(C6H8N2O2)(C2O4)2] · 2H2O and [(UO2)2(C6H8N2O2)2(H2O)3] · 2H2O. The conditions of the emergence of such coordination modes were determined. The possibility of (E/Z) izomerization of α-dioximes in reactions of uranyl complexes.