Schiff bases and their complexes with metal ions, IV - Synthesis, complex formation and spectral investigation of new tritopic bis(crown ether) compounds containing recognition sites for sodium and nickel guest cations

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

ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES, cilt.55, sa.10, ss.975-981, 2000 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 55 Sayı: 10
  • Basım Tarihi: 2000
  • Doi Numarası: 10.1515/znb-2000-1015
  • Dergi Adı: ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Index Chemicus (IC)
  • Sayfa Sayıları: ss.975-981
  • Anahtar Kelimeler: new bis(crown ether) compounds, Schiff bases, metal ion complexes, CROWN-ETHERS, BIS(BENZOCROWN ETHER)S, CRYSTAL-STRUCTURES, ALKALI-METAL, DERIVATIVES, COORDINATION, LIGAND
  • Ankara Üniversitesi Adresli: Evet

Özet

New bis(crown ether) ligands (1 - 3) of Schiff base type containing recognition sites for sodium and nickel guest cations have been synthesized by the condensation of two equivalents of 4'-formyl-5'-hydroxy(benzo-15-crown-5) with 1,5-diamino-3-azapentane, 1,8-diamino-3,6-diazaoctane or 1,8-diamino-3,6-dioxaoctane. Homonuclear ditopic crystalline 2:1 (Na+:ligand) complexes (1a - 3a) of the ligands with NaClO4 have been prepared. Heteronuclear tritopic crystalline 2:1:1 (Na+ : Ni2+ : ligand) complexes (2b and 3b) have also been synthesized from the reactions of the ditopic complexes (2a and 3a) with Ni(CH3COO)(2) . 6H(2)O. The W-VIS spectra of 1 - 3, their sodium complexes 1a - 3a and sodium-nickel complexes 2b and 3b have been recorded in polar and non-polar solvents as well as in acidic and basic media. In polar solvents and basic solutions, tautomeric equilibria (phenol-imine and keto-amine forms, O-H . . .N reversible arrow O . . .H-N) are present, depending on the hydrogen bonding. The results indicate that the concentrations of the keto forms of the compounds generally increase as the polarity of the solvent increases.