The application of catalytic ring-closing olefin metathesis to the synthesis of unsaturated oxygen heterocycles

The development of general approaches to carbon-carbon bond formation represents an important ongoing challenge for synthetic organic chemists. One efficient method for constructing carbon-carbon double bonds, the transition metal alkylidene-catalyzed olefin metathesis reaction (eq 1), has been the focus of intense interest in recent years from the standpoint of both mechanism and polymer synthesis; in contrast, use of this transformation in organic synthesis has been limited. As part of a broader program directed toward establishing transition metal alkylidenes as versatile reagents for organic chemistry, we report the successful application of catalytic olefin metathesis to the generation of a variety of unsaturated oxygen heterocycles.