Synthesis and spectral properties of tetra- and octa-substituted lead phthalocyanines

Abstract

The novel four lead phthalocyanines were prepared from three different phthalonitrile derivatives, namely 3,4-dicyanophenylmalonate, 1-chloro-3,4-dicyano-6-(1,1-dicarbethoxymethyl)benzene, 1-hexylthio-3,4-dicyano-6-(1,1-dicarbethoxy-methyl) benzene and metal salts (PbO or Pb(OAc)₂·3H₂O). Transesterification occurred when the reaction was carried out in hexanol in the presence of DBU. These new lead-phthalocyanines have been characterized by ¹H NMR, FT-IR, UV-Vis and mass spectra. Two common points in these lead phthalocyanines are intense Q band absorptions in the near-IR region and relatively lower stability of the metal ion in the phthalocyanine cavity.