Co-catalyst dependent cycloisomerization or ring closing metathesis of α,ω-dienes catalyzed by arene ruthenium complex with side-arm alcohol

Cycloisomerization and ring closing metathesis of some α,ω-dienes were catalyzed by a cationic arene ruthenium chelate complex [Ru{η 6 :η 1 -Ph(CH 2 ) 3 OH}(PCy 3 )Cl]BF 4 ( 1a ) in the presence of triethylamine and phenylacetylene, respectively, as co-catalysts. Analogous catalyst systems employing arene ruthenium cations without the side arm alcohol functional group showed lower efficiencies.