The phthalonitrile (3) including 2-(methoxymethyl)-2,3-dihydro-1,4-benzodioxane substituent and peripherally tetra substituted metal-free (4), zinc(II) (5) and magnesium(II) (6) phthalocyanines were synthesized. The photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen generation and photodegradation) properties of phthalocyanines (4-6) were examined in DMSO solutions. The zinc(II) phthalocyanine (5) showed higher singlet oxygen quantum yield (Phi(Delta)=0.82) compared to metal-free (4) (Phi(Delta)=0.13) and magnesium(II) (5) (Phi(Delta)=0.29) phthalocyanine. Also, the fluorescence quenching behaviors of phthalocyanines (4-6) by 1,4-benzoquinone (BQ) were investigated. (C) 2020 Elsevier B.V. All rights reserved.