Organophotoredox-Catalyzed Direct C-H Functionalization of “Drug Prejudice” at Room Temperature

Organophotocatalytic C─H bond functionalization has attracted lot of attention in the past several years due to the possibility of catalysing reactions in a metal-free environment. Continuing on these lines, we repot herein an organophotoredox catalyzed C─H functionalization of imidazo[1,2-a]pyridines and related heterocycles with malonates under mild conditions providing excellent yields of the products at room temperature. Although, C─3 functionalization of imidazo[1,2-a]pyridines are known, this is the first report involving malonates as coupling partners leading to the synthesis of a range of functionalized products including Zolpidem, a sedative-hypnotic medicine.