Preparation and Binding Affinity of New Porphyrin Host Molecule for Ubiquinone Analogues

Article abstract of DOI:10.1246/cl.1994.1749

αααα-meso-Tetra(7-hydroxy-1-naphthyl)porphyrin (1) is prepared as a host molecule for ubiquinone analogue, 2,3,5,6-tetramethoxy-p-benzoquinone (2).The affinity and thermodynamic aspects in porphyrin 1 - quinone 2 pairing were determined by titrimetric measyrement of electronic absorption and fluorescence spectra.The binding constant of 1 for 2 at 298 K is obtained; K_a = 7.9*10² M^-1 in toluene.The fashion of this porphyrin-quinone pairing was large different from that of previous host, αααα-meso-tetra(2-hydroxy-1-naphthyl)porphyrin (3), - quinone 2 pairing.