Phillips, Andrew D.Schreiber, DominiqueDyson, Paul J.2010-12-142010-12-142010-12-142010https://infoscience.epfl.ch/handle/20.500.14299/62131WOS:000208164703235The β-diketiminate class of ligands is renowned for the stabilization of coordinatively unsatd. main-group and transition metal complexes. Moreover, the application and scope of transition metal β-diketiminate complexes in the catalytic transformation of org. substrates is rapidly increasing. We recently reported on the synthesis, characterization and hydrogenation capabilities of a series of cationic η6-arene Ru- and Os-β-diketiminate complexes, 1. This family of complexes readily undergoes thermo-reversible [4+2] cycloaddn. with alkenes, 2 alkynes and H2 3. DFT calcns., in adjunction with high pressure NMR-deuterium labeling expts., reveal a concerted heterolytic cleavage mechanism with a low energy barrier. Now, a complete mechanistic pathway for alkene hydrogenation for complexes such as 1 has been modeled and supported by exptl. results. Furthermore, in situ NMR studies show that η6-arene hydrogenation is essential for the formation of the active catalytic species. Through steric and electronic variation of both the arene and β-diketiminate ligand, the efficiency of styrene, cyclohexene and 1-methylcyclohexene hydrogenation has been shown to be tunable, with a high turnover rate obsd. Lastly the dehydrogenation application of this family of complexes towards other types of catalysis and substrates will be discussed.Experimental and theoretical studies on the mechanism of hydrogenation by η6-arene β-diketiminato -ruthenium and -osmium complexestext::conference output::conference proceedings::conference paper