Synthesis, spectro–electrochemical properties and photoreaction with O2 of lutetium bis-ethyltetraazaporphyrin

✍ Scribed by Giampaolo Ricciardi; Sandra Belviso; Maurizio D’Auria; Francesco Lelj

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 169 KB
• Volume: 02
• Category: Article
• ISSN: 1088-4246
• DOI: 10.1002/(sici)1099-1409(199811/12)2:6<517::aid-jpp90>3.0.co;2-2

✦ Synopsis

The synthesis, spectroscopic and electrochemical properties of the Lu ( oepz )~2~ (oepz ≡ 2,3,7,8,12,13,17,18-octakis(ethyl)-5,10,15,20-porphyrazinato) complex are reported. The complex, as inferred from UV-vis spectra recorded at different concentrations, strongly aggregates in solution, the most likely association mode being dimerization. The complex shows a weak near-IR absorption (λ ~max~ = 834 nm) that is considerably blue-shifted compared with the near-IR absorption of bis(π-radical) lutetium analogues. The Lu ( oepz )~2~ neutral species is electrochemically stable between 0.73 and -0.98 V (vs Ag/AgCl), which is the largest range of stability for neutral lutetium di- tetrapyrrole complexes. Lu ( oepz )~2~ shows excellent Type II photodynamic activity, as indicated by the value of the singlet oxygen generation quantum yield φ~Δ~ of 0.94 obtained by comparison with meso-tetraphenylporphyrin.