A Facile Synthesis of Polysubstituted Pyrroles by One‐Pot Three‐Component Reaction

Abstract

A new and efficient one-pot synthesis of polysubstituted pyrrole derivatives by three-component reaction between dialkyl acetylenedicarboxylates, triphenylphosphine, 2-aminopyridin derivatives in the presence of arylglyoxals is described. The reactions were performed in dichloromethane at room temperature and neutral conditions and afforded high yields of products.

A highly efficient protocol for the synthesis of new 3-(α-aroylamido)-4-hydroxycoumarin derivatives using SnCl2–SiO2 nanoparticles under solvent-free conditions

“…Considering the above reports and in continuation of our studies on one-pot MCRs, [18][19][20] we here report for the first time a one-pot, three-component reaction of 4-hydroxycoumarin or 4-hydroxy-6-methylpyran-1-one 1, aryl glyoxals 2 and aliphatic amides 3, in the presence of SnCl 2 -SiO 2 NPs as a heterogeneous catalyst for the synthesis of 3-(α-aroylamido)-4-hydroxycoumarin derivatives 4 in solvent-free conditions (Scheme 2).…”

Recent advances in the synthesis of pyrroles by multicomponent reactions

“…79 The same group later extended this chemistry to the preparation of pyrroles bearing specific R 1 heterocyclic substituents, such as 2-(benzo)thiazolyl 80 and 2-pyridyl. 81 The same method was also found to be applicable to a-diketone substrates, leading to a route to 4,5-dialkyl-or 4,5-diarylpyrroles. 82 Glyoxal itself was also employed as one of the components of a reaction starting from aromatic amines and activated alkynes in the presence of DABCO that afforded 4-hydroxypyrroles (Scheme 62).…”

Recent advances in the synthesis of pyrroles via multicomponent reactions using arylglyoxals

“…Scheme 1. One-pot synthesis of substituted pyrroles by Anaraki-Ardakani et al 74 In a recent environmentally benign and efficient contribution to these reactions, an iodine-promoted MCR protocol was described by Musawwer Khan and co-workers for the synthesis of two kinds of pyrrole. In a facile one-pot four-component reaction between dialkyl acetylenedicarboxylate 3, aromatic amines 8 and arylglyoxals 4 catalyzed by 10 mol% of iodine in ethanol at room temperature, the 4-arylaminopyrrole-2,3dicarboxylate esters 9 were formed.…”