Iron‐MOF‐Catalyzed Domino Cyclization and Aromatization Strategy for the Synthesis of 2,4‐Diarylquinolines
Nainamalai Devarajan, Palaniswamy Suresh
Abstract
Abstract An iron‐based metal‐organic framework, Fe(BTC) has been used as an efficient heterogeneous and sustainable catalyst for the synthesis of 2,4‐diarylquinolines via three‐component Povarov reaction. The presence of a high concentration of coordinatively unsaturated Fe 3+ sites of Fe(BTC) efficiently catalyzes the formation of diarylquinolines in the presence of environmentally friendly air as an oxidant. The present methodology avoids the stoichiometric amount of catalyst and sensitive reagents. A series of 2,4‐diarylquinolines have been synthesized via Povarov synthesis in good to excellent yields with good functional group tolerance. The catalyst was easily separated by simple filtration and reused for more than five times without any remarkable loss in activity. Hot filtration test, FTIR, PXRD and SEM characterizations of reused catalyst confirmed the true heterogeneity and the stability of the catalyst. The efficiency of Fe(BTC) catalyst is compared with other homogeneous catalytic systems which enlighten the uniqueness of the present methodology.