Synthesis and Sensor Properties of Silicon Phthalocyanine Axially Substituted with Bis-(Prop-2-Ynyloxy) Groups and Polymeric Phthalocyanines Bearing PEG Substituent by “Click” Chemistry

Abstract

Synthesis and characterization of new axially substituted phthalocyanine complexes were done. Bis - (prop-2-ynyloxy) phthalocyaninato silicon (IV) compound was obtained from the reaction of 2-propin-1-ol with SiPcCl₂. Polymeric phthalocyanine containing axially substituted PEG was obtained from the reaction of bis - (prop-2-ynyloxy) phthalocyaninato silicon (IV) compound and polyethylene glycol azido. The structure of the compounds was justified by FT-IR, ¹H NMR, ¹³C NMR, UV–Vis, and mass spectra. The photophysical and photochemical properties of the phthalocyanine compound axially substituted with bis-(prop-2-ynyloxy) was investigated. Properties of the compounds were examined in terms of fluorescence quantum efficiency and singlet oxygen generating capacity, and the potential photosensitizer capacity of the compound was determined. In addition, polyethylene glycol group was added to the phthalocyanine compound by click reaction. The polymer product was obtained in blue color. Phthalocyanine(Pc) containing PEG polymeric units is soluble in dimethyl sulfoxide (DMSO). Absorption measurements of the compound at different concentrations were made. Both polyethylene glycol (PEG) and phthalocyanine compounds can be used in the manufacture of medical supplies due to their non-toxicity. UV–visible study of Bis-(prop-2-ynyloxy) phthalocyaninato silicon (IV) compound revealed its high selectivity for Fe³⁺ ion recognition.

Keywords:

• Axially phthalocyanine
• fluorescence
• “click” chemistry
• PEG aggregation
• singlet oxygen