Sustainable Synthesis of <i>N</i>-Alkyl-Pyrrolecarboxylic and Pyrrolepyrazinones Derivatives from Biosourced 3-Hydroxy-2-pyrones and Amines

Pyrroles are important compounds present in biological systems, used for drug synthesis and material chemistry. A typical strategy the pyrrolic ring formation is centered on Paal–Knorr reaction, where 1,4-dicarbonyl react with amines giving N-substituted pyrrole derivatives. Often, main problem of this approach availability appropriate carbonyl compounds. Here, we report a sustainable carboxylic acid derivatives by reaction primary 3-hydroxy-2-pyrones. These last can easily be prepared using renewable sources show property to masked that able efficiently form substituted rings. The reactions performed under conditions without solvents at 50–75 °C or basic water–methanol solutions room temperature, obtaining symmetric asymmetric pyrroles from good high yields. Moreover, dihydropyrrolepyrazinone yields 3-hydroxy-2-pyrones ethylenediamine.