Planar Trimethylenemethane Dianion Chemistry of Lanthanide Metal locenes: Synthesis, Structure, Density Functional Theory Analysis, and Reactivity of [(CMe)Lna][μ-,μ³:,μ-C(CH)] Complexes
The unusual formation of planar trimethylenemethane (TMM) dianion complexes of lanthanide metallocenes, [(CMe)Ln][μ-η³:η³-C(CH)J (Ln = Sm, 1; La, 2; Pr, 3; Nd, 4; Y, 5) has been examined by synthesizing examples with metals from La to Y to examine the effects of radial size on structure and to provi...
| Publicado en: | Journal of the American Chemical Society Vol. 128; no. 50; pp. 16178 - 16190 |
|---|---|
| Autores principales: | , , , |
| Formato: | Artículo |
| Publicado: |
American Chemical Society
12/20/2006
|
| Materias: | |
| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=23545692&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 23545692 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 12/20/2006 vid: 128 iid: 50 pid: 997 pub: American Chemical Society artinfo: ui: 23545692 10.1021/ja0645988 ppf: 16178 ppct: 12 formats: tig: atl: Planar Trimethylenemethane Dianion Chemistry of Lanthanide Metal locenes: Synthesis, Structure, Density Functional Theory Analysis, and Reactivity of [(CMe)Lna][μ-,μ³:,μ-C(CH)] Complexes aug: au: Evans, Wihiam J. Champagne, Timothy M. Ziller, Joseph W. Kaitsoyannis, Nikolas affil: Department of Chemistry, University of California, Irvine, California 92697-2025 Department of Chemistry, University College London, 20 Gordon Street, London WCIH 0Af, United Kingdom su: Organic synthesis Density functionals Functional analysis Metallocenes Rare earth metals X-ray crystallography sug: subj: Organic synthesis Density functionals Functional analysis Metallocenes Rare earth metals X-ray crystallography ab: The unusual formation of planar trimethylenemethane (TMM) dianion complexes of lanthanide metallocenes, [(CMe)Ln][μ-η³:η³-C(CH)J (Ln = Sm, 1; La, 2; Pr, 3; Nd, 4; Y, 5) has been examined by synthesizing examples with metals from La to Y to examine the effects of radial size on structure and to provide closed shell examples for direct comparison with density functional theory (DFT) calculations. Synthetic routes to 1舑4 have been expanded from the [(CMe)Ln][(μ-Ph)BPh]/neopentyl lithium reaction involving β-methyl elimination to a [(CMe)Ln][(μ-Ph)BPh]/isobutyl lithium route. The synthetic pathways are sensitive to metal radius. To obtain 5, the methylallyl complex, (CMe)Y[CHC(Me)CH], 6, was synthesized and treated with [(CMe)YH]. In the Lu case, the neopentyl complex [(CMe)LuCHC- (CH)], 7, was isolated instead of the TMM product. X-ray crystallography showed that the metrical parameters of the planar TMM dianions in each complex are similar. The structural data have been compared with DFT calculations on the closed-shell lanthanum and lutetium complexes that suggest only limited covalent interactions with the lanthanide ion. Benzophenone (2 equiv) reacts with 1 to expand the original four-carbon TMM skeleton to a dianionic bis(alkoxide) ligand containing a symmetrically substituted C= CH2 moiety in [(CMe)Sm][μ-(OCPhCH)C=CH], 8. In this reaction, the 1MM complex reacts as a bifunctional bisallylic reagent that generates an organic framework containing a central vinyl group. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2006 holdings: @attributes: islocal: N |
|---|