A Facile Synthesis of N-Substituted Pyrroles

sym-triazines. 8. Synthesis and some reactions of 4,6-disubstituted 2-(1H-pyrrolyl)-1,3,5-triazines

“…In [5] it was reported that the primary amino group of alkyl and arylamines can be used as the nitrogen component in the construction of a pyrrole ring via reaction with 2,5-dimethoxytetrahydrofuran. The latter can be used as a latent 1,4-dicarbonyl compound giving high yields of the corresponding N-alkyl-or N-arylpyrroles.…”

Five‐Membered Heterocycles: Pyrrole and Related Systems

“…A useful extension of the Paal-Knorr reaction is based on the cyclization of 2,5-dimethoxytetrahydrofuran (22) with primary amines, providing facile access to Nsubstituted pyrroles (e.g., 23) (Scheme 4.7) [76,77]. This process is further facilitated by using phosphorus pentoxide as the catalyst [78], or by heating in acetic acid under microwave conditions [79]. It has also been demonstrated that cyclizations involving 22 and amine components incorporating sensitive substituents proceeds in acceptable yields when carried out in a medium containing acetic acid and pyridine via a path featuring acid-base catalysis [80].…”

Synthesis of Heterocyclic Compounds by Carbenoid Transfer Reactions

“…2,5-Dimethoxytetrahydrofurans are masked 1,4-dicarbonyl compounds, which have been used in many reaction sequences for preparing pyrroles [72]. For example, their condensation with alkyl and arylamines, amides and sulfonamides in the presence of P 2 O 5 , readily produced Nsubstituted pyrroles in good yields [73]. Recently, Ferreira and coworkers [78,76] reported the preparation of highly substituted pyrroles (89-93, 100-101) in two-step or in onepot reactions using dihydrofurans (88) obtained from , '-diazocarbonyl derivatives (Scheme 19).…”