Mono- and Bisionic Mo- and W-Based Schrock Catalysts for Biphasic Olefin Metathesis Reactions in Ionic Liquids

Roman Schowner; Iris Elser; Florian Toth; Emmanuel Robe; Wolfgang Frey; Michael R Buchmeiser

doi:10.1002/chem.201802472

Mono- and Bisionic Mo- and W-Based Schrock Catalysts for Biphasic Olefin Metathesis Reactions in Ionic Liquids

Chemistry. 2018 Sep 6;24(50):13336-13347. doi: 10.1002/chem.201802472. Epub 2018 Aug 13.

Authors

Roman Schowner¹, Iris Elser¹, Florian Toth², Emmanuel Robe², Wolfgang Frey³, Michael R Buchmeiser¹

Affiliations

¹ Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
² XiMo Hungary Kft., Záhony u. 7, H-1031, Budapest, Hungary.
³ Institute of Organic Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany.

PMID: 29989232
DOI: 10.1002/chem.201802472

Abstract

An extensive series of the first ionic Mo- and W-based Schrock-type catalysts based on pyridinium and phosphonium tagged aryloxide ligands were prepared. Bisionic complexes of the general formula Mo(Imido)(CHR)(OR')₂ (OTf)₂ and monoionic monoaryloxide pyrrolide (pyr) (MAP-type) catalysts [M(Imido)(CHR)(OR')(pyr)⁺ ][A^- ] were successfully employed and tested in various olefin metathesis benchmark reactions under both, homogeneous and biphasic conditions using pyrrole and, for the first time with Schrock-type catalysts, ionic liquids as the polar phase. Productivities under biphasic conditions up to several thousand turn overs were achieved and are comparable to those obtained in reactions carried out in chlorobenzene or toluene. Metal contamination in the nonpolar product-containing heptane phase was <2 ppm.

Keywords: biphasic catalysis; ionic liquids; molybdenum; olefin metathesis; tungsten.

Abstract

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