Lewis Acid Catalyzed Dehydrogenative Coupling of Tertiary Propargylic Alcohols with Quinoline N-Oxides

An unprecedented Lewis acid catalyzed, high efficiency synthesis of valuable 2-(quinolin-2-yl)prop-2-en-l-ones via dehydrogenative coupling of propargylic alkynols with quinoline N-oxides is described. This protocol, which tolerates a broad range of functional groups, provides a straightforward pathway to the products 2-(quinolin-2-yl)prop-2-en-l-one scaffolds in satisfactory yields. The conversion could be scaled up to gram scale efficiently, which underlines a latent application of this methodology.