Autor(es):
Fernandes, A. ; Rosa da Costa, Ana ; Serra, Arménio C. ; Pires, Catarina
Data: 2011
Identificador Persistente: http://hdl.handle.net/10400.1/6739
Origem: Sapientia - Universidade do Algarve
Assunto(s): Catalytic transfer reduction; hydrogenation; Meso-tetraphenylchlorin; Meso-tetraphenylporphyrin; Photosensitizers; Catalytic transfer reduction; Catalytic transfer reduction; hydrogenation; hydrogenation; Meso-tetraphenylchlorin; Meso-tetraphenylchlorin; Meso-tetraphenylporphyrin; Meso-tetraphenylporphyrin; Photosensitizers; Photosensitizers
Descrição
A number of new porphyrin-based photosensitizers have been developed for Photodynamic Therapy (PDT) in recent years. Chlorins, which are a reduced form of porphyrins, show better potential of application since they have a stronger absorption band on the red region of the visible spectrum and, hence, a deeper penetration into tissues. We found that by using heterogeneous catalytic transfer reduction (CTR), meso-tetraphenylporphyrin (TPP) could be hydrogenated, although in modest yields, to meso-tetraphenylchlorin (TPC) in a single reaction step. Best reaction conditions were attained using formic acid or sodium phosphinate/water as hydrogen donors, tetrahydrofuran (THF) or toluene as solvent and 10% palladium on charcoal as catalyst.
