Redox-Neutral Three-Component Coupling of Phenacyl Azides, Aldehydes, and 1,3-Dicarbonyls to Access β-Enaminodiones.

Heating an equimolar mixture of phenacyl azides, aldehydes, and cyclic 1,3-dicarbonyls to 100 °C without any solvent, catalyst, or additive led to efficient three-component redox-neutral coupling to yield β-enaminodiones in high yields (75-86%). The scope of the synthetic method that gives dinitrogen and water as the only byproducts was successfully demonstrated by synthesizing 34 structurally diverse β-enaminodiones by taking differentially substituted phenacyl azides, aldehydes and 4-hydroxycoumarins, and 4-hydroxy-1-methylquinolin-2(1 H )-one and dimedone.