Axially Disubstituted Silicon (IV) Phthalocyanine Bearing Fluorinated Groups: Synthesis, Aggregation Behavior, and Singlet Oxygen Production Capacity

Abstract

Recent advances in fluorine-organic chemistry have significantly expanded the range of methods available for the targeted incorporation of fluorine into organic molecules. This study reports the synthesis of a novel silicon (IV) phthalocyanine (SiPc) bearing 3,5-bis(trifluoromethyl)phenoxy groups at axial positions. Characterization of SiPc was carried out by performing 1H NMR, FT-IR, and ultraviolet-visible (UV-vis) spectroscopy. Electronic absorption spectra of SiPc were recorded at various concentrations in multiple solvents to investigate the effects of concentration and solvent on aggregation behavior. The photodynamic therapy potential of SiPc was assessed by measuring its singlet-oxygen quantum yield. SiPc demonstrated high solubility at the studied concentrations in ethanol, dichloromethane, N,N-dimethylformamide, and dimethyl sulfoxide. The singlet oxygen quantum yield was determined to be 0.72, exceeding that of unsubstituted zinc(II) phthalocyanine.

Keywords

• Phthalocyanine
• Fluorine
• Aggregation
• Singlet oxygen
• Silicon

Ethical Statement

Ethics committee approval was not required for this study because there was no study on animals or humans.

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