RESUMO
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 ß-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 ß-enaminodiones by taking differentially substituted phenacyl azides, aldehydes and 4-hydroxycoumarins, and 4-hydroxy-1-methylquinolin-2(1H)-one and dimedone.
RESUMO
An efficient photocatalyst-free visible light assisted synthetic route to various (E)-stilbene derivatives was developed. The reaction proceeds through a denitrogenative photo-decomposition of vinyl azides into 2H-azirines followed by neighboring amino group assisted ring opening, 1,2-acyl migration and enolization. The photochemical reaction offers light harvesting without any photocatalyst to access a wide variety of substituted (E)-stilbenes in moderate to high yields.