We report the quantum yields for singlet oxygen production by a series of porphyrazines (pz) of the form M[pz(An; B4-n)] (Scheme 1), where the peripheral substituent A is [S-R]2 with R = (CH 2CH2O)3H, B is a fused αα′ -dialkoxybenzo group and M = 2H, Mg or Zn. These compounds show intense near-IR absorbance/emission (longest wavelength emission, ∼830 nm). Their solubilities vary with R, whereas their optical properties do not. We show that singlet oxygen sensitization by these luminescent compounds can be "tuned" from essentially off to on by varying n and selection among M = 2H, Mg or Zn. The quantum yields vary ca 60-fold within the set of compounds studied, from ψΔ = 0.007 for compound 3 to ψ Δ = ∼0.4 for compound 11.
|Original language||English (US)|
|Number of pages||4|
|Journal||Photochemistry and Photobiology|
|State||Published - Jan 2003|
ASJC Scopus subject areas
- Physical and Theoretical Chemistry