Ytterbium Trichloride-Catalyzed Diels-Alder Reactions of Unactivated Dienes

Abstract Ytterbium chloride (YbCl3) is an effective and reusable catalyst for Diels-Alder reactions of unactivated dienes with α,β-unsaturated ketones and aldehydes at room temperature, leading to products with high regio- and stereoselectivities.