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Updated: May 27, 2026

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Analogs of Grubbs' second generation catalyst with hydrophilic phosphine ligands: phase transfer activation of ring
Zhenxing Xi1, Hassan S Bazzi, John A Gladysz
1Department of Chemistry, Texas A&M University at Qatar, P.O. Box 23874, Doha, Qatar.
Abstract:
Analogs of Grubbs' second generation catalyst with hydrophilic phosphine ligands are synthesized, and those with Cy(2)PCH(2)CH(2)N(CH(3))(3)(+) Cl(-) and Cy(2)PCHCH(2)CH(2)N(CH(3))(2)(+)CH(2)CH(2) Cl(-) give much faster ring closing metatheses under CH(2)Cl(2)/aqueous or CH(2)Cl(2)/aqueous HCl biphasic as opposed to CH(2)Cl(2) monophasic conditions. This is attributed to rapid phase transfer of the dissociated ligand to the aqueous phase, where under acidic conditions it is protonated.
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