Lower rim p-tert-butylcalix[4]arene derivatives containing galactitol pendants: Complexation of 5,11,17,23-tetrakis-(1,1-dimethylethyl)-25,27-dihydroxy -26,28-bis-2-n-(1-deoxy-d-galactityl)-aminoethoxycalix[4]arene with pb(ii) and f(-i)

• PABLO J CACERES ^[1] ; JUAN COSTAMAGNA ^[1] ; ANGELA DANIL DE NAMOR ^[2] ; BETTY MATSUHIRO ^[1]
  1. [1] Universidad de Santiago de Chile

     Universidad de Santiago de Chile

     Santiago, Chile

     
  2. [2] University of Surrey

     University of Surrey

     Guildford District, Reino Unido

     
• Localización: Journal of the Chilean Chemical Society (Boletín de la Sociedad Chilena de Química), ISSN-e 0717-6309, ISSN 0366-1644, Vol. 49, Nº. 4, 2004, págs. 281-284
• Idioma: inglés
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• Resumen

  • Reductive amination of D-galactose with the bisubstituted p-tert-butylcalix[4]arylethylamine in the presence of sodium cyanoborohydride allowed the introduction of one or two galactitol residues as pendants on the lower rim. The bisubstituted secondary amine, 5,11,17,23-tetrakis-(1,1-dimethylethyl)-25,27-dihydroxy-26,28-bis-2-N-(1-deoxy-D-galactityl)-aminoethoxycalix[4]arene (III) was obtained in 24.1% yield. Complexation of this compound with Pb (II) and F(-I) was studied by ¹H-NMR and spectrophotometric titration in acetonitrile, showing a stoichiometry of 1:2 (ligand:ion) with equilibrium constants of log K1=2.22 ± 0.08 and log K2=2.07 ± 0.07 for Pb(II), and log K1=1.21 ± 0.05 and log K2=1,17 ± 0.04 for F (-I) ion