Ruthenium olefin metathesis catalysts bearing two bulky and unsymmetrical NHC ligands

The activity profile of the new indenylidene complexes containing two unsymmetrical N-heterocyclic carbene (NHC) ligands was investigated. They turned out to be effective in both straightforward olefin metathesis reactions, such as ring-closing metathesis (RCM) of diethyl diallylmalonate, as well as in more demanding processes, such as RCM of 2,2-di-(2-methylallyl)tosylate leading to a product bearing a tetrasubstituted double bond, and in selective ethenolysis of methyl and ethyl oleate