Photoinduced diversity-oriented synthesis of α-ketoester β-enamino esters, 3,3-difluoro-4-pyrrolin-2-ones, and 3-fluoro-3-pyrrolin-2-ones from bromodifluoroacetates and β-enamino esters

Diversity-oriented synthesis (DOS) has emerged as a pivotal strategy for exploring novel molecular architectures and enhancing structural diversity in chemical synthesis. In this study, we present a visible-light-driven alkoxyoxalylation and cyclization of beta-enamino esters, employing bromodifluoroacetate as a multifunctional synthon. This approach enables the efficient synthesis of diverse linear and cyclic enamine derivatives, including alpha-ketoester beta-enamino esters, 3,3-difluoro-4-pyrrolin-2-ones, and 3-fluoro-3-pyrrolin-2-ones, a class of compounds with remarkable synthetic versatility and significant pharmaceutical potential. The developed methodology features mild reaction conditions, broad substrate compatibility, operational simplicity and easy scale-up, making it highly attractive for both synthetic and medicinal chemistry.