title: RuII, IrIIIand OsIImesoionic carbene complexes: efficient catalysts for transfer hydrogenation of selected functionalities.
abstract: Pyridine-appended triazolylidene donors have been recently used as ligands in various homogeneous catalytic processes. We present here a new pyrimidine substituted triazolium salt which was prepared and used in the coordination to RuIIand OsII. The new triazolium salt and the obtained complexes were characterized by multinuclear NMR spectroscopy. The molecular composition of the mentioned compounds was confirmed by positive ion electrospray ionization (ESI+) mass spectra. The new pyrimidyl containing complexes, as well as the related pyridyl-triazolylidene containing complexes, were applied in transfer hydrogenation reactions of carbonyls, alkenes, imines and nitroarenes. The pyrimidyl containing complexes reveal an over-all better activity in comparison to their pyridine bearing analogues. The studies of electronic effects of the ligands, as well as mechanistic insights for the reduction of nitrobenzene with three selected precatalysts are presented.
authors.affiliation: Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia.
authors.forename: Aljoša
authors.initials: A
authors.lastname: Bolje
authors.affiliation: Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, D-14195 Berlin, Germany. biprajit.sarkar@fu-berlin.de.
authors.forename: Stephan
authors.initials: S
authors.lastname: Hohloch
authors.affiliation: Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia.
authors.forename: Janez
authors.initials: J
authors.lastname: Košmrlj
authors.affiliation: Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, D-14195 Berlin, Germany. biprajit.sarkar@fu-berlin.de.
authors.forename: Biprajit
authors.initials: B
authors.lastname: Sarkar