Molybdate sulfuric acid as a reusable solid catalyst in the synthesis of 2,3,4,5-tetrasubstituted pyrroles via a new one-pot [2+2+1] strategy
作者:Fatemeh Tamaddon、Mahnaz Farahi、Bahador Karami
DOI:10.1016/j.molcata.2012.01.003
日期:2012.4
Molybdatesulfuricacid (MSA) has been found as an efficient and reusable solid acid catalyst for the synthesis of new 2,3,4,5-tetrasubstituted pyrroles via a novel [2+2+1] strategy. Thus, one-pot three-component reaction of benzoin derivatives, 1,3-dicarbonyls, and ammonium acetate afforded the desired products in high yield under solvent-free conditions.
A New Three-Component Reaction Catalyzed by Silica Sulfuric Acid: Synthesis of Tetrasubstituted Pyrroles
作者:Fatemeh Tamaddon、Mahnaz Farahi
DOI:10.1055/s-0031-1290955
日期:2012.6
A novel, convenient, and efficient three-component reaction of benzoin derivatives, 1,3-dicarbonyls, and ammoniumacetate in the presence of silica sulfuric acid (SSA) is described for the synthesis of 2,3,4,5-tetrasubstituted pyrroles under solvent-free conditions.
Improved Catalyst-Free Synthesis of Pyrrole Derivatives in Aqueous Media
作者:Fatemeh Tamaddon、Farideh Amirpoor
DOI:10.1055/s-0033-1339294
日期:——
An improved catalyst-free, three-component reaction of ammonium acetate, 1,3-dicarbonyl compounds, and aromatic a-hydroxycarbonyl compounds has been carried out in water-ethanol (50:50) under reflux conditions. The improvement of yield in this aqueous medium is attributed to a combination of increased association of the reactants by hydrophobic interactions and precipitation of the product during the reaction. This operationally simple procedure is less laborious and provides a better scope and chemoselectivity than previously reported procedures.