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The Influence of Various N-Heterocyclic Carbene Ligands on Activity of Nitro-Activated Olefin Metathesis Catalysts.

ABSTRACT: A set of nitro-activated ruthenium-based Hoveyda-Grubbs type olefin metathesis catalysts bearing sterically modified N-hetero-cyclic carbene (NHC) ligands have been obtained, characterised and studied in a set of model metathesis reactions. It was found that catalysts bearing standard SIMes and SIPr ligands (4a and 4b) gave the best results in metathesis of substrates with more accessible C-C double bonds. At the same time, catalysts bearing engineered naphthyl-substituted NHC ligands (4d-e) exhibited high activity towards formation of tetrasubstituted C-C double bonds, the reaction which was traditionally Achilles' heel of the nitro-activated Hoveyda-Grubbs catalyst.

SUBMITTER: Pieczykolan M

PROVIDER: S-EPMC7287594 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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The Influence of Various N-Heterocyclic Carbene Ligands on Activity of Nitro-Activated Olefin Metathesis Catalysts.

Pieczykolan Michał M Czaban-Jóźwiak Justyna J Malinska Maura M Woźniak Krzysztof K Dorta Reto R Rybicka Anna A Kajetanowicz Anna A Grela Karol K

Molecules (Basel, Switzerland) 20200512 10

A set of nitro-activated ruthenium-based Hoveyda-Grubbs type olefin metathesis catalysts bearing sterically modified N-hetero-cyclic carbene (NHC) ligands have been obtained, characterised and studied in a set of model metathesis reactions. It was found that catalysts bearing standard SIMes and SIPr ligands (4a and 4b) gave the best results in metathesis of substrates with more accessible C-C double bonds. At the same time, catalysts bearing engineered naphthyl-substituted N ...[more]

PMID: 32408688

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