In the current study, we obtained three new catalysts containing two unsymmetrical NHC ligand moieties increasing stability of the resulted complexes, making them ideal candidates for use in reactions of demanding substrates. They have been successfully used in ring-closing metathesis leading to products with a tetrasubstituted double bond, as well as in a selective ethenolysis reaction.

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.