title: Synthesis of Highly Stable 1,3-Diaryl-1H-1,2,3-triazol-5-ylidenes and their Applications in Ruthenium-Catalyzed Olefin Metathesis.
abstract: The formal cycloaddition between 1,3-diaza-2-azoniaallene salts and alkynes or alkyne equivalents provides an efficient synthesis of 1,3-diaryl-1H-1,2,3-triazolium salts, the direct precursors of 1,2,3-triazol-5-ylidenes. These N,N-diarylated mesoionic carbenes (MICs) exhibit enhanced stability in comparison to their alkylated counterparts. Experimental and computational results confirm that these MICs act as strongly electron-donating ligands. Their increased stability allows for the preparation of ruthenium olefin metathesis catalysts that are efficient in both ring-opening and ring-closing reactions.
authors.affiliation: UCR-CNRS Joint Research Chemistry Laboratory (UMI 2957), Department of Chemistry, University of California, Riverside, CA 92521, Arnold and Mabel Beckman Laboratories of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, and Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35032 Marburg, Germany.
authors.forename: Jean
authors.initials: J
authors.lastname: Bouffard
authors.forename: Benjamin K
authors.initials: BK
authors.lastname: Keitz
authors.forename: Ralf
authors.initials: R
authors.lastname: Tonner
authors.forename: Vincent
authors.initials: V
authors.lastname: Lavallo
authors.forename: Gregorio
authors.initials: G
authors.lastname: Guisado-Barrios
authors.forename: Gernot
authors.initials: G
authors.lastname: Frenking
authors.forename: Robert H
authors.initials: RH
authors.lastname: Grubbs
authors.forename: Guy
authors.initials: G
authors.lastname: Bertrand