Direkte Bildung von 2,5‐Dimethyl‐3,3a,4‐trithia‐1‐azapentalenium‐ und 4,6‐Dimethyl‐3‐thioxo‐3H‐1,2‐dithiolo‐[4,3‐c]pyridinium‐Ionen aus Acetonitril und Schwefel‐wasserstoff. Die Kristallstrukturen ihrer Salze mit [UBr₆]^2⊖ bzw. [UO₂Br₄]^2⊖

Abstract

Crystal Structures of their Compounds with [UBrslZa and [U0zBr4]2QThe heterocyclic title cations 1 and 2 are formed, along with other products, as [UBr6IzQ and [U02Br4]2Q compounds, resp., by the reaction of H2S with a solution of uranium pentabromide in acetonitrile. Their crystal structures were determined by X-ray diffraction.(1)2[UBr6] has planar cations 1 in which the sulfur atoms lie along straight line but with rather different S -S distances.Durch Reaktionen von Schwefelwasserstoff mit Halogeniden wie z. B. NbC15 oder WBr6 in wasserfreien Losungsmitteln konnen Thiohalogenide oder Thiohalogenkomplexe erhalten werden'). Entsprechende Reaktionen mit Uranhalogeniden haben sich bislang als schwer kontrollierbar erwiesen, weshalb wir Versuche mit mehreren Losungsmitteln ausprobiert haben. Bei Verwendung von Acetonitril sind wir dabei auf die Titelverbindungen gestol3en.

Tetrahalide Complexes of the [U(NR)2]2+ Ion: Synthesis, Theory, and Chlorine K-Edge X-ray Absorption Spectroscopy

“…As expected, our DFT calculations for [UO 2 Cl 4 ] 2– show strong mixing in a D 4 h ligand field with the axial oxo ligands. Consistent with previous reports, the U–O interaction is characterized by six antibonding orbitals of 2 e u (5f π ), 1 a 2 u (5f σ ), 1 a 1 g (6d σ ), and 1 e g (6d π ) symmetry, Figure . − ,− In comparison to the highly covalent U–O bonds, the equatorial Cl ligands are calculated to form U–Cl interactions that have far less Cl 3p-character. The Cl 3p σ-type symmetry-adapted linear combinations (SALCs) of atomic orbitals span e u + a 1 g + b 1 g symmetries and can mix with U 5f and 6d orbitals to form U–Cl σ-bonding interactions of 2 e u (U–Cl 5f σ , U–O 5f π ), 1 a 1 g (U–Cl 6d σ , U–O 6d σ ), and 1 b 1 g (U–Cl 6d σ , U–O 6d δ ) symmetries (Figure and Table ).…”

“…Theoretical and experimental studies on the uranyl ion, [UO 2 ] 2+ , have provided foundational models for understanding electronic structure and bonding in molecular actinide science. − Of particular interest are their relevance to understanding the environmental speciation of [UO 2 ] 2+ , its role in nuclear fuel reprocessing schemes, and its potential as a photocatalyst for solar fuel formation. − In the course of studying [UO 2 ] 2+ , the series of dianionic uranyl(VI) tetrahalides[UO 2 X 4 ] 2– (X = Cl, Br, I)have emerged as popular analytes for spectroscopic and computational studies. − ,− These highly symmetric D 4 h compounds are attractive because they can be prepared in high yields, can be isolated as large single crystals, and are air and moisture stable. Of equal importance, the tetrahalide derivatives can be used as convenient aqueous and nonaqueous starting materials in uranium(VI) synthetic schemes. − …”

Synthesis and crystal structure of triethylammonium hexabromidouranate(IV) dichloromethane monosolvate

“…The C-HÁ Á ÁBr hydrogen bonds in (Ph 3 EtP) 2 [UBr 6 ](Caira et al, 1978) range from 2.782 (1) to 3.504 (2) Å . An example for N-HÁ Á ÁBr hydrogen bonds is (C 6 H 8 NS 3 ) 2 [UBr 6 ](Conradi et al, 1986), with lengths of 2.81 (9) Å for the interactions. These bond lengths are comparable with the presented data.1588 Deubner et al (C 6 H 16 N) 2 [UBr 6 ]ÁCH 2 Cl 2 Acta Cryst.…”