Catalytic Multicomponent Synthesis of Highly Substituted Pyrroles Utilizing a One-Pot Sila-Stetter/Paal−Knorr Strategy
作者:Ashwin R. Bharadwaj、Karl A. Scheidt
DOI:10.1021/ol049044t
日期:2004.7.1
[reaction: see text] A multicomponent synthesis of highly substituted pyrroles catalyzed by thiazolium salts has been disclosed. The reaction employs an acyl anion conjugateaddition reaction of acylsilanes (sila-Stetter) and unsaturated ketones to generate 1,4-dicarbonyl compounds in situ. The subsequent addition of various amines promotes a Paal-Knorr reaction, affording the desired pyrrole nucleus
Boehmite nanoparticles (AlOOH NPs) was found to be a highly active and green catalyst for the synthesis of highlysubstitutedimidazoles under solvent-free conditions. This one-pot procedure is very simple, and affords good to excellent yields. Furthermore, the catalyst shows good thermal stability and recyclability. The catalyst was recycled for five runs without an appreciable loss in its catalytic