Heterogeneous silica-supported copper catalyst for the ultrasound-mediated rapid reaction between dimedone, formaldehyde, and amines at room temperature
acidity in comparison to pure silica, which is reflected in the sonication-assisted rapid reactionbetween dimedone, formaldehyde, and amines. Sonication-mediated room temperature synthesis was proved to be more convenient and rapid than ordinary stirring. A standard leaching experiment proved that the reaction was heterogeneous with this recyclable catalyst. Graphical abstract
Multicomponent Reactions of 1,3-Cyclohexanediones and Formaldehyde in Glycerol: Stabilization of Paraformaldehyde in Glycerol Resulted from using Dimedone as Substrate
作者:Minghao Li、Chang Chen、Fei He、Yanlong Gu
DOI:10.1002/adsc.200900770
日期:2010.2.15
Glycerol has proved to be an effective promoting medium for many multicomponentreactions of 1,3-cyclohexanediones and formaldehyde. Styrenes, amines, 2-naphthol, 4-hydroxy-6-methyl-2-pyrone and 4-hydroxy-1-methyl-2-quinolone could easily react with 1,3-cyclohexanediones and paraformaldehyde in glycerol under catalyst-free conditions to afford a variety of complex skeletons in fair to excellent yields