ZfN: Search Results

1	Author	R. D. Fischer, E. Klähne, J. Kopf	Requires cookie*
	Title	Halogeno-und Pseudohalogeno-tris(pentahaptocyclopentadienyl)uran(IV)- Komplexe als Lewis-Säuren: Darstellung und Struktur trigonal-bipyramidaler Uran-Organyle des Typs [(rj 5 -C5H5)3UXL] Tris(pentahaptocyclopentadienyl)uranium(IV) Halides and Pseudohalides as Lewis-Acids: Preparation and Structure of Uranium Organyls [(^-C5H5)3UXL] with Trigonal-Bipyramidal Coordination
	Abstract	The first two examples of a novel series of organo-actinide complexes, [CpsUXL] (Cp = r/ 5 -CoH5, X = halide or pseudohalide anion, L = uncharged Lewis base), are described. The X-ray structure analysis of the system with X = NCS and L = CH3CN confirms an almost linear alignment (H3)CCNUNCS along with the coplanarity of the three Cp ring normals. The remarkable Lewis acidity of certain CpsUX-compounds appears to be essential for the formation of oligomeric species [Cp3UX]oo as well as for specific reactions of monomeric CP3UX.
	Reference	Z. Naturforsch. 33b, 1393—1397 (1978); eingegangen am 17. Juli 1978
	Published	1978
	Keywords	Uranium Organyls, Cyclopentadienyl Ligand, Crystal Structure
	Similar Items	Find
	DEBUG INFO
	TEI-XML for	default:Reihe_B/33/ZNB-1978-33b-1393.pdf
	Identifier	ZNB-1978-33b-1393
	Volume	33

2	Author	R. Dieter Fischer+, Kenan Yünlü	Requires cookie*
	Title	Zum ambidenten Charakter des Cyanotrihydroborat-Liganden in Uran(IV)-Organylen On the Ambident Nature of the Cyanotrihydroborate Ligand in Organouranium(IV) Complexes
	Abstract	Both the acceptedly oligomeric complex [(CsHs^U^-NCBHs)],} (1) and its hitherto unknown, appreciably more soluble and volatile homologue, [(CHaCaH^U^-NCBHa)]« (2), display NIR/VIS spectra typical of trigonal bipyramidal (tbp) metal coordination in the solid state, but of pseudotetrahedral (v>-Td) coordination e.g. in CH2CI2 and C6H5CH3 solution. The X H NMR spectra of 2 in these non coordinating solvents can be best explained in terms of temperature dependent equilibria involving the two rapidly interconverting y-Td-isomers (CHgCsH^U^-HaBCN) and (CH3C5H4)3UNCBH3. A reversible colour change: green ^ brown at 130-150 °C also suggests the facile rupture of U-H and U-N bonds, respectively, in thermally excited, polycrystalline (2).
	Reference	Z. Naturforsch. 38b, 1369—1374 (1983); eingegangen am 6. Juli 1983
	Published	1983
	Keywords	Uranium Organyls, Cyanotrihydroborate Ligand, NMR of Paramagnetic Species, Solution Equilibria
	Similar Items	Find
	DEBUG INFO
	TEI-XML for	default:Reihe_B/38/ZNB-1983-38b-1369.pdf
	Identifier	ZNB-1983-38b-1369
	Volume	38