Synthesis, Photo-, and Ionochromic Properties of Indolyl(thienyl)maleimides with Terpyridine Receptor

Abstract

Indolyl(thienyl)maleimides with terpyridine receptor in the bridge part have been synthesized. Irradiation of their toluene solutions with light at λ = 436 nm has led to the formation of cyclic isomers. The reverse ring opening reaction has occurred during the photolysis with visible light (λ > 500 nm). 1-(4-([2,2′:6′,2″-Terpyridin]-4′-yl)phenyl)derivatives have exhibited the properties of chromogenic naked-eye sensors to Fe²⁺ cations in acetonitrile solution, changing the solution color from bright-orange to red.