Unveiling the role of ancillary ligands in acceptorless benzyl alcohol dehydrogenation and etherification mediated by mesoionic carbene iridium complexes. Issue 1 (4th December 2017)

• Record Type: Journal Article
• Authors: Vivancos, Ángela; Petronilho, Ana; Cardoso, Joao; Müller-Bunz, Helge; Albrecht, Martin
• Is Part Of: Dalton transactions. Volume 47:Issue 1(2017)
• Page Start: 74
• Page End: 82
• Publication Date: 2017-12-04
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c7dt04109h
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : We synthesized a set of triazolylidene iridium(iii ) complexes [IrCp*(C^N)L] n + containing different neutral or anionic ancillary ligands L and demonstrated their impact on the catalytic activity in alcohol conversion. Abstract : We synthesized a set of triazolylidene iridium(iii ) complexes [IrCp*(C^N)L] n + (Cp* = pentamethylcyclopentadienyl, C^N = C, N-bidentate coordinating pyridyl-triazolylidene) containing different neutral or anionic ancillary ligands L and evaluated their impact on the catalytic activity in alcohol conversion. We demonstrate that these ancillary ligands have a strong influence on the catalytic selectivity and direct whether the iridium center preferentially catalyzes either the dehydrogenation or the dehydration of benzyl alcohol. Ligand exchange experiments provide a direct correlation of ligand lability with catalytic activity and selectivity. These results underline the relevance of ancillary ligands and provide a rational approach to tailor the catalytic activity of the iridium center towards aldehyde formation (loss of H2 ) or etherification (elimination of H2 O).