1235552-79-0Relevant academic research and scientific papers
Synthesis and characterization of monoisomeric 1,8,15,22-substituted (A3B and A2B2) phthalocyanines and phthalocyanine-fullerene dyads
Ranta, Jenni,Kumpulainen, Tatu,Lemmetyinen, Helge,Efimov, Alexander
experimental part, p. 5178 - 5194 (2010/10/03)
(Figure presented) Synthesis and characterization of three phthalocyanine-fullerene (Pc-C60) dyads, corresponding monoisomeric phthalocyanines (Pc), and building blocks, phthalonitriles, are described. Six novel bisaryl phthalonitriles were prepared by the Suzuki-Miyaura coupling reaction from trifluoromethanesulfonic acid 2,3-dicyanophenyl ester and various oxaborolanes. Two phthalonitriles were selected for the synthesis of A 3B- and A2B2-type phthalocyanines. Phthalonitrile 4 has a bulky 3,5-di-tert-butylphenyl substituent at the α-phthalo position, which forces only one regioisomer to form and greatly increases the solubility of phthalocyanine. Phthalonitrile 8 has a 3-phenylpropanol side chain at the α-position making further modifications of the side group possible. Synthesized monoisomeric A3B- and A 2B2-type phthalocyanines are modified by attachment of malonic residues. Finally, fullerene is covalently linked to phthalocyanine with one or two malonic bridges to produce Pc-C60 dyads. Due to the monoisomeric structure and increased solubility of phthalocyanines, the quality of NMR spectra of the compounds is enhanced significantly, making detailed NMR analysis of the structures possible. The synthesized dyads have different orientations of phthalocyanine and fullerene, which strongly influence the electron transfer (ET) from phthalocyanine to fullerene moiety. Fluorescence quenchings of the dyads were measured in both polar and nonpolar solvents, and in all cases, the quenching was more efficient in the polar environment. As expected, most efficient fluorescence quenching was observed for dyad 20b, with two linkers and phthalocyanine and fullerene in face-to-face orientation.
