Sequential ring-closing metathesis and silicon-assisted cross-coupling reactions: Stereocontrolled synthesis of highly substituted unsaturated alcohols

A sequential ring closing metathesis/silicon-assisted cross-coupling sequence has been developed, Alkenyldimethylsilyl ethers of omega -unsaturated alcohols undergo facile ring closure with Schrock's catalyst to afford five-, six-, and seven-membered cycloalkenylsiloxanes bearing substituents on both alkenyl carbons. These siloxanes were highly effective coupling partners with various aryl and alkenyl halides and in the presence of Pd(0) afforded styrenes and dienes in high yield and specificity and with good functional group compatibility.