Synthesis of phthalocyanines with tridentate branched bulky and alkylthio groups

The synthesis and characterisation of 4,5-octasubstituted metal free and metallo (Zn^II and Co^II) phthalocyanines carrying four alkylthio groups and four tridentate NNS substituents on periferal positions are reported. The distinct differences encountered in the newly synthesized compounds with four alkyl chains are their high solubility in common organic solvents, e.g. chloroform, dichlorometane, THF, acetone, DMF and DMSO and bathochromic shifts in the UV-Vis spectra in comparison with 4,5-substituted analogues with four chloro groups in addition to four branched bulky groups. ¹H NMR spectroscopy also shows a smaller up field shift in all protons for newly synthesised phthalocyanines with respect to the latter compounds.