Ruthenium-Catalyzed Oxypropargylation of Alkenes

The ruthenium-catalyzed oxypropargylation of alkenes with propargylic alcohols and simple alcohols has been found via ruthenium-allenylidene complexes as key intermediates. As a synthetic application, an intramolecular cyclization using this method has been developed to give the corresponding anti-1-alkoxy-3-ethynylindanes in high to excellent yields with a high diastereoselectivity.