221105-29-9Relevant academic research and scientific papers
Syntheses of ruthenium(II) complexes containing polyphosphine ligands and their applications in the homogeneous hydrogenation
Sung, Kie-Muon,Huh, Seong,Jun, Moo-Jin
, p. 469 - 479 (1998)
A series of ruthenium(II) complexes of polyphosphine ligands, RuHCl(CO)(etp) (2), RuHCl(CO)(tdpme) (3) and RuHCl(PP3) (4) [etp PhP(CH2CH2PPh2)2; tdpme = CH3C(CH2PPh2)3; PP3 = P(CH2CH2PPh2)3] have been prepared from RuHCl(CO)(AsPh3)3 (1) through typical substitution reactions and characterized by spectroscopic (IR and 1H NMR) methods and elemental analyses. These compounds have been used as catalyst precursors in the homogeneous hydrogenation of cyclohexene, cyclohexanone, propanal and 2-cyclohexen-l-one. These polyphosphine Ru(Il) complexes show enhanced catalytic activities in comparison with monodentate or bidentate phosphine or arsine analogues. The selectivities of compound 3 for substrates have been found to decrease in the order cyclohexanone > propanal > cyclohexene. In the case of hydrogenation of 2-cyclohexen-l-one, cyclohexanol has been produced by way of cyclohexanone. The catalytic activities are directly proportional to the concentration of catalysts. The dependence of catalytic activities upon the hydrogen pressure has been also studied. The Arrhenius activation energy of cyclohexanone for compound 3 is found to be Ea = 97.2 kJ mol-1 and the activation parameters are ΔH? = 94.0 kJ mol-1 and ΔS? = -0.72kJ K-1 mol-1. 1999 Elsevier Science Ltd. All rights reserved.
