Selective Access to Trisubstituted Macrocyclic <i>E</i>- and <i>Z</i>‑Alkenes from the Ring-Closing Metathesis of Vinylsiloxanes

Abstract

Macrocyclic (<i>E</i>)-alkenylsiloxanes, obtained from <i>E</i>-selective ring-closing metathesis reactions, can be converted to the corresponding (<i>Z</i>)-alkenyl bromides and (<i>E</i>)-alkenyl iodides allowing access to both <i>E-</i> and <i>Z</i>-trisubstituted macrocyclic alkenes. The reaction conditions and substrate scope of these stereoselective transformations are explored