Relay Ring‐Closing Metathesis—A Strategy for Achieving Reactivity and Selectivity in Metathesis Chemistry

How can uncooperative alkenes be rendered more susceptible to metathesis reactions? The realization that what is difficult in an intermolecular sense can become straightforward when transposed to a kinetically favorable intramolecular reaction has led to development of relay ring-closing metathesis (see scheme). This provides a method for directing initiation and propagation of previously unattainable metathesis sequences.