Copper‐Catalyzed Multicomponent Synthesis of Fluorescent 2′‐Phenyl‐1′ H ‐spiro[fluorene‐9,4′‐naphtho[2,3‐ h ]quinoline]‐7′,12′‐dione Derivatives

Copper‐catalyzed multicomponent coupling reactions between ketones, alkynes, and amines (KA 2 coupling) by using 9‐fluorenones 1a – 1e , aryl alkynes 2a – 2g , and amino anthraquinones 3a and 3b afforded the highly conjugated, fluorescent spirofluorenonaphthoquinoline derivatives 4a – 4r in very good yields. The products obtained from 1‐aminoanthraquinone ( 3a ) and 1,4‐diaminoanthraquinone ( 3b ) appear different in color but both series of products show emission in the red region. An analogous reaction with 1‐aminopyrene ( 5 ) afforded the highly fluorescent hybrid pyrene‐fluorenone spirocycle derivative 6 , which shows emission in the deep blue region.