Pure and Applied Chemistry

Abstract: The use of photoresponsive hexatriene architectures to regulate chemical reactivity is described. The major focus of this report is how the two isomers of dithienylethene derivatives exhibit different steric and electronic properties. The ring-open form is structurally flexible, and the thiophene rings are electronically insulated from each other, while the ring-closed counterpart has a rigid structure, and there is a linear π-conjugated pathway along the molecular backbone. Representative examples that demonstrate how these photoswitches can be used to influence metal coordination, catalysis, and nucleophilicity are highlighted in this overview.