Near-IR absorbing phthalocyanines

Phthalocyanines with four or eight hexylthio-substituents on the periphery were prepared by cyclotetramerization of 4-hexylthio-1,2-dicyanobenzene and 4,5-bis(hexylthio)-1,2-dicyanobenzene. The new compounds were characterized by elemental analyses, 1H NMR, IR and UV–VIS spectral data. The electronic spectra exhibit intense Q band near-IR region at 720 nm for the tetrahexylthio-substituted phthalocyanine and at 739 nm for the octa-substituted one together with less intense B band near UV range.