I2-Promoted Povarov Multicomponent Reaction for the Synthesis of 2,2′-Biquinolines and N-Heteroaromatic Benzothiazoles

An efficient I₂-promoted Povarov multicomponent reaction for the synthesis of 2,2′-biquinolines or N-heteroaromatic benzothiazole using 2-methylquinoline or 2-methylbenzo[d]thiazole, arylamines, and α-ketoesters was developed. The methyl group of methyl aza-arenes incorporated in the Povarov reaction via an iodination/Kornblum oxidation sequence. This method was achieved through a one-pot two-step process without the need for transition metals, demonstrating excellent scalability in synthesis.