Development of an efficient biocatalytic three-component reaction for synthesizing pyrrole derivatives

Multi-component reactions (MCRs) enable the development of efficient and atom-economic methods for synthesizing pyrrole derivatives. However, the current MCRs methods for synthesizing pyrrole derivatives in the enzymatic process have been unexploited. Herein, we developed a one-pot three-component enzymatic promiscuous catalytic system with green, efficient, and atom-economic to construct pyrrole derivatives. In this system, amines and 1,3-dicarbonyl compounds formed enamines with subsequent Michael addition with nitroolefins catalyzed by trypsin. A series of pyrrole derivatives were successfully obtained with moderate to good yield (up to 92 %). In addition, molecular simulations were conducted to gain insight into the source of differing tolerance of aromatic amides and fatty amines and the intrinsic effect of solvents in this system. This enzymatic catalytic one-pot three-component system has excellent functional tolerance, simple operation, and application potential for industrial production demonstrated by the gram scale experiment.