| Autor: |
Rocha BG; Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal. fatima.guedes@tecnico.ulisboa.pt pombeiro@tecnico.ulisboa.pt., Mac Leod TC, Guedes da Silva MF, Luzyanin KV, Martins LM, Pombeiro AJ |
| Jazyk: |
angličtina |
| Zdroj: |
Dalton transactions (Cambridge, England : 2003) [Dalton Trans] 2014 Oct 28; Vol. 43 (40), pp. 15192-200. Date of Electronic Publication: 2014 Sep 03. |
| DOI: |
10.1039/c4dt01509f |
| Abstrakt: |
The Ni(II) and Zn(II) complexes [MCl(Tpms(Ph))] (Tpms(Ph) = SO3C(pz(Ph))3, pz = pyrazolyl; M = Ni 2 or Zn 3) and the Cu(II) complex [CuCl(Tpms(Ph))(H2O)] (4) have been prepared by treatment of the lithium salt of the sterically demanding and coordination flexible tris(3-phenyl-1-pyrazolyl)methanesulfonate (Tpms(Ph))(-) (1) with the respective metal chlorides. The (Tpms(Ph))(-) ligand shows the N3 or N2O coordination modes in 2 and 3 or in 4, respectively. Upon reaction of 2 and 3 with Ag(CF3SO3) in acetonitrile the complexes [M(Tpms(Ph))(MeCN)](CF3SO3) (M = Ni 5 or Zn 6, respectively) were formed. The compounds were obtained in good yields and characterized by analytic and spectral (IR, (1)H and (13)C{(1)H} NMR, ESI-MS) data, density functional theory (DFT) methods and {for 4 and [(n)Bu4N](Tpms(Ph)) (7), the latter obtained upon Li(+) replacement by [(n)Bu4N](+) in Li(Tpms(Ph))} by single crystal X-ray diffraction analysis. The Zn(II) and Cu(II) complexes (3 and 4, respectively) act as efficient catalyst precursors for the diastereoselective nitroaldol reaction of benzaldehydes and nitroethane to the corresponding β-nitroalkanols (up to 99% yield, at room temperature) with diastereoselectivity towards the formation of the anti isomer, whereas the Ni(II) complex 2 only shows a modest catalytic activity. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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