title: Synthesis and spectroscopic characterization of two tetrasubstituted cationic porphyrin derivatives.
abstract: An imidazolium tetrasubstituted cationic porphyrin derivative (the free base and its Zn(II) complex) with five-membered heterocyclic groups in the meso-positions were synthesized using microwave irradiation, and the compounds obtained characterized by (1)H-NMR and mass spectrometry. We observed that under microwave irradiation the yield is similar to when the synthesis is performed under conventional heating, however, the time required to prepare the porphyrins decreases enormously. In order to investigate the electronic state of these compounds, we employed UV-Vis and fluorescence spectroscopy combined with quantum chemical calculations. The results reveal the presence, in both compounds, of a large number of electronic states involving the association between the Soret and a blue-shifted band. The Soret band in both compounds also shows a considerable solvent dependence. As for emission, these compounds present low quantum yield at room temperature and no solvent influence on the fluorescence spectra was observed.
authors: Laboratório de Fotoquímica, Instituto de Química, Universidade Federal de Uberlândia, P.O. Box 593, CEP 38400-902 Uberlândia, Minas Gerais, Brazil. aeduardo@ufu.br
authors: Antonio E H
authors: AE
authors: Machado
authors: Weverson R
authors: WR
authors: Gomes
authors: Diesley M S
authors: DM
authors: Araújo
authors: Hércules S
authors: HS
authors: Miglio
authors: Leonardo T
authors: LT
authors: Ueno
authors: Rodrigo
authors: R
authors: De Paula
authors: José A S
authors: JA
authors: Cavaleiro
authors: Newton M
authors: NM
authors: Barbosa Neto
mesh_terms: D009682:Magnetic Resonance Spectroscopy; D011166:Porphyrins / Q000138:chemical synthesis* / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
chemical_list: D011166:Porphyrins