Porphyrins and Phthalocyanines as Chromogenic Anion Sensors

Abstract

Porphyrins (Por) and phthalocyanines (Pc) possess unique physico-chemical properties which make them valuable compounds in different scientific fields, namely in medicine, catalysis, solar energy converters, etc. 2 Recently, we have found that Por and Pc can be used as scaffolds to prepare novel chromogenic anion-binding agents that can be used to build functional materials capable of removing anionic pollutants from contaminated water. New chemosensors capable of sensing targeted guests via changes in their optical properties have attracted considerable attention due to their potential applications in the development of analytical devices. Species capable of selectively recognizing anionic substrates are of interest due to their importance in areas as diverse as nuclear waste treatment, environmental chemistry, and biology. The design of chemosensor materials thus represents an important field of research in organic chemistry. At present interest in such systems is increased due to a need to find, inter alia, methods for waste treatment. Ideally, artificial anion chemosensors should have an ability to selectively recognize and sense anionic analytes using naked eye detectable color changes, or via an easy-tomonitor electrochemical or spectroscopic response. 3