Synthesis and properties of 1-(2-bromoethyl)-, 1-(2-alkoxyethyl)- and 1-(2-dialkylaminoethyl)2-alkylpyrroles

A Novel Cu-Assisted Cycloisomerization of Alkynyl Imines: Efficient Synthesis of Pyrroles and Pyrrole-Containing Heterocycles

“…Most known methods for the construction of the pyrrole ring proceed via various types of cycloaddition or cycloisomerization of acyclic precursors ,2a, and are most effective for forming 2,5-di- or polysubstituted pyrroles. To the best of our knowledge, there are no convenient methods for the formation of a monosubstituted pyrrole ring . Herein we wish to report a novel, general, and efficient method for the construction of 2-monosubstituted and 2,5-disubstituted pyrroles, as well as fused aromatic heterocycles containing a pyrrole ring, via the Cu-assisted cycloisomerization of readily available alkynyl imines.…”

Synthesis and properties of 3-alkyl(aryl)-5-(dimethylaminomethyl)pyrazoles

“…Antipyretic, analgesic, anti-inflammatory, and other pyrazole-based drugs are known [2][3][4][5][6]. Reactions of β-chlorovinyl ketones with hydrazine hydrate lead to the formation of 3-substituted pyrazoles [7], whereas 4-chlorobut-2-en-1-ones react with hydrazine hydrate to produce 1-amino-2-alkylpyrroles [8]. 1-Substituted 3,4,4-trichlorobut-3-en-1ones were reported to react with hydrazine to give 3-aryl-5-(dichloromethyl)pyrazoles whose subsequent condensation with hydrazine at a ratio of 2 : 1 afforded 1,2-bis[(3-aryl-1H-pyrazol-5-yl)methylidene]hydrazines [9].…”