New 1,1′‐Ring‐substituted Vanadocene Dichlorides. Crystal structures of [V(η⁵‐C₅H₄SiMe₃)₂Cl₂] and [V(η⁵‐C₅H₅)₂Cl₂]

Abstract

The 1 ,I '-ring-substituted vanadocene dichlorides crystallizes with two crystallographically independent molecules [V(q5-C5H,R)2C12] (R = CMe,, SiMe,, SiEt,) have been in its monoclinic unit cell. These two molecules are quite similar prepared from VCl, and the appropriate lithiated cyclopenta-in their essential structuraleatures. Compound 3 crystallizes in diene, C5H,RLi, in 1 : 2 ratios. All complexes were characteriz-the triclinic space group P 1. The trimethylsilylcyclopentadienyl ed by elemental microanalysis and IR spectroscopy. The crystal rings are bound in a staggered relative orientation. structures of [V($-C5H4SiMe3)2C1Z] 3 and the parent compound [V($-C5H5)2Cl,] 1 have been determined by X-ray dif-Neue 1,l' 4ngsubstituierte Vanadocendichloride. Kristallstrukturen von [V(q5-C5H,SiMe,),C121 und [V(q5-C,H5),C121Inhaltsiibersicht. Die 1,l '-ringsubstiuierten Vanadocendihalo-wartungen. Verbindung 1 kristallisiert mit zwei kristallogragenide [V($-C5H4R)2ClZ] (R = CMe,, SiMe,, SiEt,) wurden phisch unabhangigen Molekiilen in ihrer monoklinen Elemenaus VCl, und dem geeigneten lithiierten Cyclopentadien, tarzelle. Diese zwei Molekiile sind ganz ahnlich in ihren C5H,RLi, im Molverhaltnis 1 : 2 dargestellt. Alle Komplexe wesentlichen strukturellen Merkmalen. Verbindung 3 wurden elementaranalytisch und IR spektroskopisch charak-kristallisiert in der triklinen Raumgruppe Pi. Die Trimethylterisiert. Die Kristallstrukturen von [V(q5-C5H,SiMe,),ClZ] 3 silylcyclopentadienylringe sind in einer gestaffelten relativen und der Stammverbindung [V(q5-C5HJZClZ] 1 wurden durch Orientierung am Metal1 gebunden. Rontgenstrukturanalysen bestimmt und entsprechen den Er-

Electronic structure of the d1 bent-metallocene Cp2VCl2: A photoelectron and density functional study

“…The calculated structures of Cp 2 VCl 2 and Cp 2 VCl are compared with the reported structures determined from X-ray crystallography in Table 3 [23,24]. The structures agree reasonably well with the largest deviation being the V-Cl bond distance in Cp 2 VCl 2 which is underestimated by only about 0.04 Å.…”

Magnetic Anisotropy of Dichlorobis(η5‐cyclopentadienyl) Complexes of Vanadium, Niobium, and Tantalum

“…Based on the available spectroscopic data,7,8 a concept is available to predict the magnetic behavior of metallocene halides. So, an essential precondition is fulfilled to evaluate magnetic effects in exchange‐coupled systems involving such molecules as magnetically active partner 4…”

“…Structural and Physical Techniques: The crystal structures of the compounds under investigation are known by single‐crystal X‐ray diffraction 4–6. X‐ray powder data were recorded to characterize the samples with a STADI‐P2 diffractometer (STOE, Germany) with Ge monochromated Cu‐ K α 1 radiation and positional sensitive detector.…”

“…In particular vanadium species play an important role in the synthesis of molecular magnetic materials 2,3. Whereas crystal structures,4–6 spectroscopic data (EPR7,8), and d–d transition energies9 of MCp 2 Cl 2 [M = V ( 1 ), Nb ( 2 ), and Ta ( 3 )] are known in whole or in part, precise magnetic susceptibility data as a function of temperature are scarce. Therefore, since the elucidation of the magnetic properties of these mononuclear molecules may be useful for clarifying their role in spin‐spin exchange coupled systems, we have investigated their magnetic behavior.…”

Solid State Structure of Bis[(bromo)(dicyclopentadienyl)vanadium(μ2-fluoro)][(bromo)(cyclopentadienyl)vanadium][tetrafluoroborate]

“…For vanadium, the dichloride [1], dibromide [2], and diiodide [3] are all known and the dibromide [4], the dichloride, and some alkyl-substituted analogues [5][6][7][8] have been crystallographically characterized. No structures have been reported for any mixed species, nor for fluoride complexes, with the exception of species having two AsF 5 or SbF 5 fragments linked to the fluorides [9,10].…”