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Modified N-Heterocyclic Carbene Ligand for the Recovery of Olefin Metathesis Catalysts via Noncovalent Host-Guest Interactions.

ABSTRACT: A general method, focusing upon olefin metathesis, was developed for the recovery of homogeneous olefin metathesis catalysts from crude reaction solutions. This method utilizes the supramolecular host-guest interaction between an azobenzene-modified N-heterocyclic carbene ligand and a silica-grafted ?-cyclodextrin to remove homogeneous catalyst in a heterogeneous manner, allowing for the recovery of more than 97% of ruthenium in solution. The robust and simple nature of the guest molecule allows for the application of this method to a wide range of homogeneous catalysts. This study reports the synthesis and characterization of the said precatalyst and host compound as well as proof-of-concept recovery trials for a number of common substrates, with the residual ruthenium content of reaction mixtures evaluated by inductively coupled plasma mass spectrometry.

SUBMITTER: Ondrusek BA

PROVIDER: S-EPMC6641285 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Modified N-Heterocyclic Carbene Ligand for the Recovery of Olefin Metathesis Catalysts via Noncovalent Host-Guest Interactions.

Ondrusek Brian A BA Chung Hoyong H

ACS omega 20170726 7

A general method, focusing upon olefin metathesis, was developed for the recovery of homogeneous olefin metathesis catalysts from crude reaction solutions. This method utilizes the supramolecular host-guest interaction between an azobenzene-modified N-heterocyclic carbene ligand and a silica-grafted β-cyclodextrin to remove homogeneous catalyst in a heterogeneous manner, allowing for the recovery of more than 97% of ruthenium in solution. The robust and simple nature of the guest molecule ...[more]

PMID: 31457699

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