Novel photochromic compounds based on the 1-thienyl-2-vinylcyclopentene backbone.

[reaction: see text] A new class of photochromic compounds based on the hexatriene backbone has been developed. The backbone, composed of a thiophene ring, a perfluorocyclopentene ring, and a trisubstituted olefin, undergoes reversible ring-opening and ring-closing photoisomerization reactions when irradiated with ultraviolet and visible light, respectively.