Thermal Cycloreversion Reaction of a Photochromic Dithienylperfluorocyclopentene with tert-Butoxy Substituents at the Reactive Carbons

tert-Butoxy groups were introduced at 2 and 2′-positions of the thiophene rings of a dithienylperfluorocyclopentene to prepare a photochromic compound with a thermal cycloreversion reactivity and a low photocycloreversion quantum yield. The cycloreversion quantum yield was similar to the isopropyl-substituted derivative and the half-life time of the colored isomer at 100 °C was 8 s.