Kinetically controlled cross-metathesis reactions with high E-olefin selectivities.

[reaction: see text] Homoallylic alcohols with anti-allylic substituents display enhanced E-olefin selectivity in cross-metathesis (CM) reactions with allyltrimethylsilane. The high selectivity can be explained via a five-membered chelate intermediate in which the hydroxyl group of the homoallylic alcohol coordinates to the ruthenium metal center of Grubbs' catalyst.