from first principles PP-I-1

OP-II-4Diphenylphosphinoferrocenyl Thioether Diene Rh(I) and Ir(I) CatalyzedKetone Hydrogenation: Turning Precatalysts into Active SpeciesBelkova N.V. 1 , Kozinets E.M. 1,2 , Filippov O.A. 1 , Fekete M. 3 , Duckett S.B. 3 , Manoury E. 2 ,Poli R. 2 , Shubina E.S. 11 A.N. Nesmeyanov Institute of Organoelement Compounds RAS, Moscow, Russia2 Laboratoire de Chimie de Coordination CNRS, Toulouse, France3 Department of Chemistry, University of York, United Kingdomnataliabelk@ineos.ac.ruIridium diene complexes with diphenylphosphinoferrocenyl thioether ligands (Scheme 1) areeffective catalysts for ketone asymmetric hydrogenation (Scheme 2) [1]. The analoguesrhodium complexes synthesized for the first time [2] are good structural and functionalmodels of these catalysts.FeRXSM = Ir, RhMPX = Cl, BFPh 42= NBD, CODXX=H, Me, Cl, FO0,2%FeRS ClIrPPh 2H 2 (30 bar)iPrOH, MeONa, 8h, 10°CScheme 1 Scheme 2XyieldeeOH>99%>99%The hydrogenation of these precatalytic species under stoichiometric conditions (1-3 bars H 2 )was studied by NMR and UV/Vis spectroscopy. The reaction does not proceed in CH 2 Cl 2when well dried hydrogen is used and features an induction period in the presence of alcohol(MeOH, iPrOH) or H 2 O. The use of ROD or D 2 O shortens the induction period and reducesthe hydrogenation rate. The effect of the diene ligand and anion, solvent and added base(pyridine, MeONa) on the hydrogenation rate was also investigated. The reaction generates adihydride species, which is stabilized in the presence of pyridine as shown by parahydrogenNMR measurements. Combined with DFT calculations these experimental data contribute toelucidate the precatalyst activation mechanism.Acknowledgment: We thank the CNRS and the RFBR for support through a bilateral grant,the GDRI “Homogeneous Catalysis for Sustainable Development”, and the French Embassyin Moscow for the financial support of joint PhD thesis for EMK.References:[1] E. Le Roux, R. Malacea, E. Manoury, R. Poli, L. Gonsalvi, M. Peruzzini, Adv. Synth. Catal., 349(2007) 309.[2] E. M. Kozinets, O. Konev, O. A. Filippov, J.-C. Daran, R. Poli, E. S. Shubina, N V. Belkova,E. Manoury, (2012) submitted39