Synthesis, characterization, and electrochemical, electrical and gas sensing properties of a novel tert-butylcalix[4]arene bridged bis double-decker lutetium(III) phthalocyanine

Ceyhan T., Altındal A., ÖZKAYA A. R., Erbil M. K., Bekaroǧlu Ö.

Polyhedron, vol.26, no.1, pp.73-84, 2007 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 26 Issue: 1
  • Publication Date: 2007
  • Doi Number: 10.1016/j.poly.2006.07.035
  • Journal Name: Polyhedron
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.73-84
  • Keywords: Calix[4]arene, Cyclic voltammetry, Double decker, Gas sensing, Phthalocyanine
  • Istanbul Technical University Affiliated: Yes


A novel tert-butylcalix[4]arene bridged bis double-decker lutetium(III) phthalocyanine (Lu2Pc4) (5) has been synthesized by the reaction of dimeric lutetium(III) phthalocyanine (4) with two equiv. of dilithium octakis hexylthiophthalocyanine in amyl alcohol. The phthalonitrile derivative 1 was obtained through the displacement reaction of 4-nitrophthalonitrile with 1,3-dimethoxy-4-tert-butylcalix[4]arene and was converted to the isoindoline derivative 2 by bubbling ammonia gas in dry MeOH. Compound 4 was prepared from 2, 4,5-bis(hexylthio)-1,2-diiminoisoindoline (3), and lutetium acetate in dry DMF. The new compounds and phthalocyanines were characterized by elemental analysis, IR, UV-Vis, 1H NMR, ESR and MALDI-TOF MS spectra. The electrochemical properties of 4 and 5 have been examined by cyclic voltammetry, and compared. Distinctive differences between the voltammetric behaviour of 4 and 5 were detected. These differences were compatible with the structures of the compounds. A detailed study of the effect of temperature on the d.c. conductivity and impedance spectra (40-105 Hz) of spin coated films of 4 and 5 at temperatures between 290 K and 420 K was carried out. By analyzing the d.c. electrical behaviour of the 5 film, it was found that the experimental data are described by a thermally activated conductivity dependence on temperature with an activation energy of 0.77 eV. The a.c. results give a power law behaviour, σa.c. = A(T)ωs, in which the frequency exponent s decreases with temperature. The sensing behaviour of the film for the online detection of volatile organic solvent vapors was investigated by utilizing an AT-cut quartz crystal resonator. It was observed that the adsorption of the target molecules on the coating surface cause a reversible negative frequency shift of the resonator. Thus, a variety of solvent vapors can be detected by using the 5 film as sensitive coating, with sensitivity in the ppm and response times in the order of several seconds depending on the dipole moment of the organic solvent. © 2006 Elsevier Ltd. All rights reserved.