Novel distyryl BODIPY–fullerene dyads: preparation, characterization and photosensitized singlet oxygen generation efficiency

Abstract

Novel types of mono- and bis-distyryl-BODIPY–fullerene dyads, 6 and 7, were prepared by Bingel cyclopropanation. Distyryl-BODIPY derivative (3) was reacted with methyl malonyl chloride and malonyl dichloride respectively for the synthesis of compounds 4 and 5 as light-harvesting antennae that contain one and two BODIPY units. Through the Bingel cyclopropanation of these BODIPYs (4 and 5) with fullerene-C₆₀ in the presence of CBr₄ and DBU, distyryl-BODIPY–fullerene dyads 6 and 7 were obtained. All newly synthesized compounds were characterized by MALDI-MS, ¹H and ¹³C NMR and elemental analysis. Moreover, the photophysical and photochemical properties of these heavy atom free dyads were investigated for the determination of their photosensitizer and fluorescence abilities in the near IR region to generate singlet oxygen.