60176-19-4Relevant articles and documents
Direct Synthesis of Pyrroles via Heterogeneous Catalytic Condensation of Anilines with Bioderived Furans
Tao, Lei,Wang, Zi-Jian,Yan, Tian-Hao,Liu, Yong-Mei,He, He-Yong,Cao, Yong
, p. 959 - 964 (2017/08/09)
Given the wide applications of pyrroles in agriculture, pharmaceuticals, and supramolecular and materials chemistry, a mild and eco-friendly route to produce functionalized pyrroles from bioderived feedstocks is highly desirable. Described herein is a mild and convenient synthesis of pyrroles via direct condensation of an equimolar amount of structurally diverse anilines with biobased furans catalyzed by a simple and efficient solid acid H form zeolite Y catalyst. The protocol tolerates a large variety of functional groups and offers a general and versatile method for scale-up synthesis of a variety of N-substituted pyrrole compounds. Most importantly, the bioactive pyrrole-derived drug pyrvinium, which has lately been confirmed as highly effective in curing colon cancer, can be obtained by this method.
Indium-Catalyzed Formal N-Arylation and N-Alkylation of Pyrroles with Amines
Yonekura, Kyohei,Oki, Kenji,Tsuchimoto, Teruhisa
, p. 2895 - 2902 (2016/09/16)
Under indium Lewis acid catalysis, a nitrogen atom of N-unsubstituted pyrroles was replaced with a nitrogen atom of primary amines, thereby producing N-aryl- and N-alkylpyrroles. This system formally introducing such carbon frameworks to the pyrrole nitrogen atom shows unique selectivity: only the H?N(pyrrolyl) unit undergoes the N-arylation and N-alkylation even in the coexistence of a similar H?N(indolyl) part; and an aryl–halogen bond remains intact. These are clearly different from the typical method depending on the C?N(pyrrolyl) bond-forming reaction with organic halides as substrates. From a viewpoint of pyrrole N-protection–deprotection chemistry, worth noting is that a methyl group on the pyrrole nitrogen atom can be removed, albeit in a formal way. (Figure presented.).
Modified Paal-Knorr synthesis of novel and known pyrroles using tungstate sulfuric acid as a recyclable catalyst
Karami, Bahador,Jamshidi, Masih,Khodabakhshi, Saeed
, p. 12 - 16 (2013/07/26)
Tungstate sulfuric acid (TSA) as a solid acid catalyst has been synthesized and used in Paal-Knorr synthesis of some novel and known pyrroles under solvent-free conditions. Catalyst loadings can be as low as 1 mol percent to give high yields of the corresponding pyrroles at 60 °C. To make the catalyst, sodium tungstic reacted with chlorosulfonic acid in nhexane.
