Synthesis and characterization of new bis(crown ether)s of Schiff base type containing recognition sites for sodium and nickel guest cations

Hayvali Z., Gunduz N., Kilic Z., Weber E.

JOURNAL FUR PRAKTISCHE CHEMIE-CHEMIKER-ZEITUNG, cilt.341, sa.6, ss.568-573, 1999 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 341 Sayı: 6
  • Basım Tarihi: 1999
  • Dergi Adı: JOURNAL FUR PRAKTISCHE CHEMIE-CHEMIKER-ZEITUNG
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Index Chemicus (IC)
  • Sayfa Sayıları: ss.568-573
  • Anahtar Kelimeler: crown compounds, Schiff bases, tautomerism, metal ion complexes, spectroscopy, ALKALI-METAL CATIONS, CROWN ETHERS, BIS(BENZOCROWN ETHER)S, COMPLEXATION, EXTRACTION, CRYSTAL, LIGANDS, IONS
  • Ankara Üniversitesi Adresli: Evet

Özet

New bis(crown ether) ligands of Schiff base type (2-4) containing recognition sites for sodium and nickel guest cations have been synthesized by the condensations of two equivalents of 4'-formyl-5'-hydroxy(benzo-15-crown-5) (1) with diamines, H2N-(CH2)(n)-NH2 (n = 2-4). Homonuclear ditopic crystalline 2 : I (Na+ : ligand) complexes (2a-4a, 2b-4b! of the ligands with NaSCN and NaClO4 have been prepared. The NaClO4, complexes of 3 and 4 (3b and 4b) form heteronuclear tritopic crystalline complexes with Ni-2 circle plus cations of stoichiometry 2 : 1 : 1 (Na-circle plus : Ni-2 circle plus : Ligand). A homonuclear monotopic Ni-2 circle plus complex has also been prepared by the reaction with Ni(CH3COO), 6H(2)O. The UV-VIS spectra of 2-4 and their NaClO4, complexes (2b-4b) are studied in different solvents including acidic and basic media. In polar solvents, tautomeric equilibria (phenol-imine, O-H ... N and ketoamine, O ... H-N forms) are present, as supported by the UV-VIS data.