A Novel Fluorescent Skeleton from Disubstituted Thiochromenones via Nickel-Catalyzed Cycloaddition of Sulfobenzoic Anhydrides with Alkynes.

Nickel-catalyzed cycloaddition of alkynes and 2-sulfobenzoic anhydrides gives highly functionalized thiochromenones. The reaction undergoes a deoxygenative rather than decarbonylative pathway and shows advantages of an excellent isolated yield (up to 95%), high reaction efficiency, and high regioselectivity. As one of the resulted products, 2,3-di(triphenylamine)-thiolchromenone possesses a typical aggregation-induced emission property and emits efficient near-infrared fluorescence.