A novel approach to fluorescent photochromic fulgides

Oxidation of the cyclic sulfide group of 3-(2-methylbenzo[b]thienyl)fulgide into the sulfone one affords 3-[1-(2-methyl-1,1-dioxidobenzo[b]thiophen-3-yl)ethylidene]-4-(propan-2-ylidene)dihydrofuran-2,5-dione, a new photochromic fulgide that displays photomodulated fluorescence properties.