Abstract

A series of meso-substituted phenyl porphyrin derivatives were selected for investigating their photochromic behavior in several aryl chloride solutions. After ultraviolet irradiation (UVI, λ = 360 nm), the solutions’ color changed rapidly and sensitively from pink to bright green; and their pink color can be recovered gradually when the green samples are radiated under visible light (VR, λ > 500 nm) or placed around diffused light at ambient conditions. Notably this photochromic behavior can be completely stimulated by a halochromic method. A porphyrin H₂TMPP 3 was selected as a typical sample for revealing this chromic mechanism, and molecular configuration for the green porphyrin chromophores was proposed based on crystal assembly of H₂TPP 1. Finally the sensitive molecular recognition of H₂TMPP 3 towards hydrochlorides was examined.

Keywords: Halochromism, molecular recognition, photochromism, ultraviolet irradiation, visible radiation.

Graphical Abstract