Crystal structure of the La3+ sandwich complex based on 8-membered macrocyclic siloxanolate ligands

Igonin, V. A.; Lindeman, Sergey V.; Struchkov, Yu. T.; Shchegolikhina, Olga I.; Molodtsova, Yulia A.; Pozdnyakova, Yu. A.; Zhdanov, A. A.

doi:10.1007/bf00700002

Cited by 23 publications

(15 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is in marked contrast to all previous cases in which the silylamide route was employed to prepare salt-free lanthanide complexes. [27] In our hands, control experiments using sublimed Ln[N(SiMe 3 ) 2 ] 3 precursors thus far did not produce any characterizable lanthanide disiloxanediolates. Another interesting result of the present study is the finding that the nature of the products strongly depends on both the stoichiometry of the precursors and the size of the Ln 3 ion.…”

Section: Resultsmentioning

confidence: 56%

“…A more straightforward preparation involves treatment of [(C 5 Me 5 ) 2 Sm(m-H)] 2 with hexamethylcyclotrisiloxane in THF solution. [26] Somewhat related are a series of highly interesting lanthanide complexes containing cyclo(poly)siloxanolate ligands which were reported by Zhdanov et al [27] We describe here the synthesis of novel lanthanide complexes derived from [(Ph 2 SiO) 2 O] 2À as well as the first scandium and uranium derivatives.…”

Section: Introductionmentioning

confidence: 85%

See 1 more Smart Citation

f-Element Disiloxanediolates: Novel Si−O-based Inorganic Heterocycles

Lorenz¹,

Fischer²,

Jacob³

et al. 2001

Chem. Eur. J.

View full text Add to dashboard Cite

The preparation and structural characterization of scandium and f-element complexes derived from the disiloxanediolate dianion, [(Ph2SiO)2O]2-, are reported. Reactions of in situ prepared Ln[N(SiMe3)2]3 (Ln = Eu, Sm, Gd) with (Ph2SiOH)2O in different stoichiometries afforded the lanthanide disiloxanediolates [Eu[[(Ph2SiO)2O]Li(Et2O)]3] (1), [[[(Ph2SiO)2O]Li(dme)]2SmCl(dme)] (2), and [[[((Ph2SiO)2O]Li(thf)2]2GdN(SiMe3)2] (3). In situ formed (Ph2SiOLi)2O reacted with anhydrous NdBr3 (molar ratio 3:1) to give polymeric [[Nd[(Ph2SiO)2O]3[mu-Li(thf)]2[mu2LiBrLi(thf)(Et2O)]]n] (4). Treatment of 3 with Ph2Si(OH)2 in the presence of acetonitrile yielded the dilithium trisiloxanediolate derivative [[Ph2Si(OSiPh2O)2][Li(MeCN)]2]2 (5), which according to an X-ray analysis displays an Li4O4 heterocubane structure. The trinuclear scandium complex [[[(Ph2SiO)2O]Sc(acac)2]2Sc(acac)] (6) was obtained by reaction of [(C5Me5)Sc(acac)2] (C5Me5 = eta5-pentamethylcyclopentadienyl) with (Ph2SiOH)2O in a 3:2 molar ratio. Selective formation of the colorless uranium(VI) derivative [U[Ph2Si(OSiPh20)2]2[(Ph2SiO)2O]] (7) was observed when uranocene, U(eta8-C8H8)2, was allowed to react with (Ph2SiOH)2O. An X-ray diffraction study of the solvated derivative [U[Ph2Si(OSiPh2O)2]2[(Ph2SiO)2O]].Et2O.TMEDA (TMEDA= N,N,N',N'-tetramethyl-ethylenediamine) (7a) revealed the presence of both the original [(Ph2SiO)2O]2- dianion as well as the ring-enlarged [Ph2Si(OSiPh2O)2]2- ligand in the same molecule.

show abstract

Section: Resultsmentioning

confidence: 56%

Section: Introductionmentioning

confidence: 85%

f-Element Disiloxanediolates: Novel Si−O-based Inorganic Heterocycles

Lorenz¹,

Fischer²,

Jacob³

et al. 2001

Chem. Eur. J.

View full text Add to dashboard Cite

show abstract

“…Although we were neither able to locate the additional proton directly in a difference Fourier map nor to deduce its position from careful analysis of bond distances, it is reasonable to assume that it resides either on the central oxygen atom or, like in 4, on one of the m 2 -oxygens which connect adjacent yttrium atoms (in which case the absence of any marked irregularity in Y-O bond distances may be explained by a disorder of the protonation site over eight equivalent oxygen atom positions); both oxide and hydroxide centred lanthanide complexes with a central, square planar OM 4 core have precedence in the literature. 14 The infrared spectrum of [5]Cl 3 displays a weak band around 3354 cm À1 which is in the range for alcoholic or phenolic OH-stretching frequencies, but lacks a sharp peak around 3580 cm À1 which had been previously assigned to the stretching of m 3 -OH groups. 14,15 Although this finding favours a structure with an oxide-centred core and one protonated catecholate unit, it must be noted that a m-OH band is not always visible, in particular when additional water is present 16 (which is also the case here), so that unambiguous assignment of the protonation site remains unfeasible.…”

Section: Resultsmentioning

confidence: 94%

Stoichiometry controlled self-assembly of tri- and octa-nuclear palladium–yttrium complexes

2010

View full text Add to dashboard Cite

Palladium complexes with template-centred, bidentate bis-phosphine donors were prepared in a one-step process via base-assisted condensation of a ditopic catechol phosphine 1 (LH 2 ) with simple yttrium and palladium salts. It was found that the assembly of either one or two Pd-bisphosphine units on one template was possible in a controlled way by adjusting the stoichiometric ratio of the reactants. Thus, reaction of YCl 3 , (cod)PdCl 2 , and 1 in a 1 : 4 : 2 molar ratio produced a complex of composition [Y(H 2 L 2 Pd)(L 2 Pd)(dmf)]Cl whereas reaction of the same reactants in 1 : 2 : 1 molar ratio gave a polynuclear assembly [O(YL 2 Pd) 4 (dmf) 4 H]Cl 3 . Both products were characterised by single-crystal X-ray diffraction studies and spectroscopic data (NMR, ESI-MS) which indicated that the assemblies found in the crystalline state persist also in solution.Scheme 1

show abstract

“…A Na ion (located on a twofold rotation axis with 1/2 site occupancy factor) balances the charge. The structure of 1 is quite different from those of the [22], they are both the tetrameric Nd complexes with O bridges. However, the differences between above two complexes are also significant.…”

Section: Resultsmentioning

confidence: 92%