Substituent effects on the spectral properties of some 3-substituted formazans

Tezcan H., Ozkan N.

DYES AND PIGMENTS, cilt.56, sa.2, ss.159-166, 2003 (SCI İndekslerine Giren Dergi) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 56 Konu: 2
  • Basım Tarihi: 2003
  • Doi Numarası: 10.1016/s0143-7208(02)00131-6
  • Sayfa Sayıları: ss.159-166


In this study, 3-substitutedphenyl-1,5-diphenylformazans were synthesized with -NO2 and -COOH groups in the o-, m- and p- positions of the 3-phenyl ring. Their structures were elucidated from elemental analysis , H-1 NMR, C-13 NMR and IR spectra. The dependence lambda(max) upon the type of the substituents and their positions on the phenyl ring was investigated using UV-vis spectra. If was observed that there was a shift of lambda(max) towards the blue region with the electron withdrawing -NO2 and -COOH groups. The size of this' chemical shift (Deltalambda(max)) was dependent upon the type and position of the substituent on the 3-phenyl ring. A linear relation was obtained between the substituent effect and the Hammett substituent coefficients. (C) 2002 Elsevier Science Ltd. All rights reserved.