124206-22-0Relevant academic research and scientific papers
Synthesis and 171Yb- Nuclear Magnetic Resonance Spectra of Ytterbium(II) Aryloxides and 2> (X = OR' or NR2) (R' = C6H2Bu-t2-2,6-Me-4, R = SiMe3, thf = tetrahydrofuran)
Hende, Johannes R. van den,Hitchcock, Peter B.,Holmes, Stephen A.,Lappert, Michael F.
, p. 1435 - 1440 (1995)
Crystalline homo- and hetero-leptic ytterbium(II) aryloxides derived from bulky 2,6-di-tert-butyl-4-methylphenol (R'OH) were prepared as follows: (a) 1 from 2 R'OH and I (R = SiMe3); (b) 2> 2 by desolvating 1 or from 2> II and 4 R'OH; and (c) 2> 3 from II and 2 R'OH or II and 2.Single-crystal X-ray diffraction studies established complex 1 to be monomeric with a distorted tetrahedral configuration and 2 to be dimeric with asymmetrically bridging -OR' ligands.Complexes 1-3 were characterised by multinuclear (1H, 13C, 29Si and 171Yb) NMR spectroscopy and elemental (C, N, H) analysis.Variable-temperature 1H and 13C NMR spectral data for 2 led to ΔG(excit) for the terminal/bridge -OR' site-exchange process.The known aryloxide 4 was obtained from 1 and an excess of tetrahydrofuran (thf); reacting 1 with the appropriate stoichiometric amount of thf, pyridine (py) or 1,2-bis(dimethylphosphino)ethane (dmpe) yielded 5, 6 or 7, respectively.The δ > NMR spectral data for complexes 4-7 showed that displacement of diethyl ether from 1 (δ 238 at 193 K) by another neutral coligand had a marked effect on the magnitude of the chemical shift, ranging from δ 286 at 233 K for 4 to δ 999 at 296 K for 7.
Four-and five-co-ordinate lanthanide (II) aryloxides: X-ray structures of the bis(2,6-di-t-butyl-4-methylphenoxo)ytterbium(II) complexes [Yb(OAr) 2(L)2] and [Yb(OAr)2(L′)3] [Ar=C6H2But
Deacon, Glen B.,Hitchcock, Peter B.,Holmes, Stephen A.,Lappert, Michael F.,MacKinnon, Peter,Newnham, Russell H.
, p. 935 - 937 (2007/10/02)
General methods for the preparation of hydrocarbon-soluble, monomeric ytterbium (II) aryloxides are described {Yb+2TIOAr, or [Yb(NR2) 2(OEt2)2]+2ArOH;R=SiMe3, Ar=C 6H2But/s
