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

Heating an equimolar mixture of phenacyl azides, aldehydes, and cyclic 1,3-dicarbonyls to 100 degrees C without any solvent, catalyst, or additive led to efficient three-component redox-neutral coupling to yield fi- 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 fi-enaminodiones by taking differentially substituted phenacyl azides, aldehydes and 4-hydroxycoumarins, and 4-hydroxy-1-methylquinolin-2(1H)-one and dimedone.

Automated summary

Heating a mixture of phenacyl azides, aldehydes, and cyclic 1,3-dicarbonyls without any solvent, catalyst, or additive at 100 degrees C led to efficient three-component redox-neutral coupling to yield fi-enaminodiones with high yields (75-86%). The synthesis of 34 structurally diverse fi-enaminodiones was demonstrated by using differentially substituted phenacyl azides, aldehydes, 4-hydroxycoumarins, and 4-hydroxy-1-methylquinolin-2(1H)-one, and dimedone as substrates, with dinitrogen and water as the only byproducts.