Subphthalocyanine-based conjugated porous polymers for efficient singlet oxygen generation†
Two subphthalocyanine (SubPc)-based conjugated porous polymers, SubPc-P1 and SubPc-P2, have been designed and synthesized by an A3 + B2 and A4 + B2 type Sonogashira cross-coupling reaction, in which axial coupling is absent and present, respectively. These two polymers exhibit Brunauer–Emmett–Teller surface areas of 434 m2 g−1 and 106 m2 g−1, respectively. Combining their porosity with strong light harvesting capability, SubPc-P1 and SubPc-P2 can efficiently absorb long-wavelength photons even in the near-infrared region to generate singlet oxygen rapidly. In addition, compared with SubPc-P2, SubPc-P1 shows red-shifted light absorption and a larger specific surface area, which agrees well with the better singlet oxygen generation ability upon irradiation at 690 nm.