title: New indenylidene-type metathesis catalysts bearing unsymmetricalN-heterocyclic ligands with mesityl and nitrobenzyl substituents.
abstract: New indenylidene-type second generation catalysts bearing modified unsymmetrically substitutedN-heterocyclic carbene ligands were synthesized. The complexes contain anN-mesityl andN'-nitrobenzyl substituted NHC ligand. The precursors of free carbenes-imidazolinium salts-were obtained in an easy and environment-friendly way (under aqueous or neat conditions). The new catalysts were prepared by reaction of in situ generated carbenes with a 1st generation indenylidene catalyst, containing pyridine ligands instead of tricyclohexylphosphine. The complexes were tested in RCM, CM, and ene-yne metathesis model reactions in commercial-grade solvents in air. Their activities were compared with that of commercially available indenylidene catalyst. The structures of complexes and their stability were investigated using static DFT calculations with mixed basis set.
authors.affiliation: Institute of Chemistry, University of Białystok, Ciołkowskiego 1K, 15-245 Białystok, Poland.
authors.forename: Marta
authors.initials: M
authors.lastname: Malinowska
authors.affiliation: Institute of Chemistry, University of Białystok, Ciołkowskiego 1K, 15-245 Białystok, Poland.
authors.forename: Mariana
authors.initials: M
authors.lastname: Kozlowska
authors.affiliation: Institute of Chemistry, University of Białystok, Ciołkowskiego 1K, 15-245 Białystok, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Hryniewicka
authors.affiliation: Institute of Chemistry, University of Białystok, Ciołkowskiego 1K, 15-245 Białystok, Poland.
authors.forename: Stanisław
authors.initials: S
authors.lastname: Witkowski
authors.affiliation: Institute of Chemistry, University of Białystok, Ciołkowskiego 1K, 15-245 Białystok, Poland.
authors.forename: Jacek W
authors.initials: JW
authors.lastname: Morzycki
keywords: DFT calculations; Metathesis; N-Heterocyclic carbenes; Nitro compounds; Ruthenium catalyst