Unusual reactivity of 1-aminoanthraquinone in copper catalyzed multicomponent reaction with isatins and aryl alkynes: synthesis and photophysical properties of regioisomeric fluorescent 3-spiroheterocyclic 2-oxindoles

Unusual reactivity of 1-aminoanthraquinone with a number of isatins and aryl alkynes in a copper catalyzed multicomponent reaction afforded a novel, highly conjugated, and separable regioisomers of 3-spiroheterocyclic 2-oxindoles in excellent combined yield. Both the regioisomers exhibited considerable optical properties and found as fluorescence materials. Based on experimental observation, a plausible reaction mechanism has been proposed.