The Green Synthesis of 2‐Pyrrolin‐5‐ones from Bio‐renewable Glyoxal, Diketones and Amines

Described herein is an effective and green reaction between diketones, amines and bio‐renewable glyoxal, affording a wide range of 2‐pyrrolin‐5‐ones and releasing water as the only byproduct. The reaction features step‐economy, high efficiency, mild conditions, broad substrate scope, hazardous waste avoiding and easy scale‐up. The further transformation between the products and aldehydes can be potentially applied for fluorescent dye synthesis. An efficient and environmentally benign method was developed for the synthesis of 2‐pyrrolin‐5‐ones from dicarbonyl compounds, bio‐renewable glyoxal, and amines. More than 25 new 2‐pyrrolin‐5‐one compounds were synthesized in good to high yields under mild conditions.