Abstract
A simple and efficient synthesis of pyrrolo[1,2-a]pyrazine using Schiff base formation, intramolecular cyclization (or N-alkylation), and Pictet–Spengler type reaction (hetero-aromatisation) has been developed. In this chemistry, metal-free, cost and time-effective processes have been highlighted to afford the complex nitrogenous scaffold using simple starting materials.
Graphical Abstract
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