Synthesis of a fluorescein–porphyrin hybrid and its supramolecular self-assembly with amino-porphyrinatocopper(II) by hydrogen bonding

A fluorescein–porphyrin hybrid (Fl-PTPP) has been synthesized and characterized by UV/Vis, IR, 1H NMR, ES-MS and elemental analysis. The supramolecular self-assembly of Fl-PTPP with the copper(II) complex of 5-(p-amino-phenyl)-10,15,20-triphenylporphyrin, (CuAPTPP), by hydoxyl-amino type hydrogen bonding was studied using vapor pressure osmometry (VPO) measurements, ES-MS, UV/Vis, 1H NMR and fluorescence spectroscopic titration. The data indicate formation of a (Fl-PTPP)–CuAPTPP supramolecular complex. Fluorescence strengthening character was observed in a spectroscopic titration experiment for the Fl-PTPP/CuAPTPP system. The association constant of the supramolecular complex was calculated from the fluorescence titration data, and found to be less than that of a carboxyl–carboxyl type hydrogen-bonding system.