1095062-41-1Relevant articles and documents
RhCl(CO)(PPh3)2.
Yamakawa,Katsurao,Shinoda,Saito
, p. 183 - 186 (1987)
Exclusive evolution of hydrogen without carbon monoxide was observed for the liquid-phase dehydrogenation of 2-propanol with trans- left bracket RhCl(CO)(PPh//3)//2 right bracket under MLCT irradiation, suggesting the catalytic role of the photogenerated left bracket RhCl(PPh//3)//2 right bracket species before its rapid replenishment with CO ligand. A quantum efficiency exceeding unity (1. 6) was obtained at 364 nm and 108 degree C in refluxing solution mixed with diglyme. Homogeneous photocatalysis in the visible region was discussed from the standpoint of energy storing.
Organosilicon Chemistry. Part 24. Homogeneous Rhodium-catalysed Hydrosilation of Alkenes and Alkynes: The Role of Oxygen or Hydroperoxides
Dickers, Hugh M.,Haszeldine, Robert N.,Malkin, Leslie S.,Mather, Adrian P.,Parish, R. V. (Dick)
, p. 308 - 313 (1980)
The hydrosilation of propene, hex-1-ene, and hex-1-yne, catalysed by has been reinvestigated.When all reagents are carefully purified, the hydrosilation reaction is completely inhibited but can be initiated by the addition of oxygen or t-butyl hydroperoxide.The rate and extent of reaction in the latter case is unaffected by the presence of phenolic radical traps.For optimum reaction, stoicheiometric quantities of hydroperoxide are required.In the hex-1-yne system, variation of the PPh3:Rh ratio gives maximum activity at 1:1 and, with this stoicheiometry, the reaction rate is relatively insensitive to purification of the reagents.It is suggested that the role of oxygen or hydroperoxide is to remove triphenylphosphine from the system, by oxidation, generating a highly active catalyst with a low PPh3:Rh ratio.In the 'clean' conditions isomerisation of hex-1-ene proceeds rapidly, being catalysed by the silyl complex .
Alkene and dihydrogen formation by catalytic dehydrogenation of alkane with RhCl(PR3)2 photo-generated from RhCl(CO)(PR3)2
Nomura, Kotohiro,Saito, Yasukazu
, p. 57 - 64 (2008/10/08)
Alkene and dihydrogen formation by photocatalytic dehydrogenation of alkanes using RhC1(CO)(PR3)2 proceeded with high turnover frequencies, amounting to 1404 h-1 for nonane at nonane at 135 ΔRG (PR3 = PMe3
Reaction Dynamics of the Tricoordinate Intermediates MCl(PPh3)2 (M = Rh, or Ir) as Probed by the Flash Photolysis of the Carbonyls MCl(CO)(PPh3)2
Wink, David A.,Ford, Peter C.
, p. 436 - 442 (2007/10/02)
Reported is a kinetics flash photolysis investigation of the rhodium(I) complex RhCl(CO)(PPh3)2 in benzene solution.These results are interpreted in terms of the transient formation of the unsaturated species RhCl(PPh3)2 (A), an intermediate crucial to proposed mechanisms of Wilkinson's catalyst reactions such as olefin hydrogenation, but which has not been the subject of previous direct investigation.Kinetics of the dimerization of A and of the reactions of this transient with CO, C2H4, PPh3, and H2 are also described.The second-order rate constant for the reaction with H2 is 1.0E5/M.s in good agreement with the value >7E4/M.s estimatted by Halpern and Wong (J.Chem.Soc., Chem.Commun. 1973, 629) from kinetics investigations of the hydrogenation of RhCl(PPh3)3.Furthermore, the equilibrium constant for triphenylphosphine dissociation from RhCl(PPh3)3 can be calculated as 2.3E-7 M from the ratio of the first-order dissociation rate constant 0.68/s determined by those workers and the second-order rate constant 3.0E6/M.s for the back reaction determined here.Rates of the subsequent reactions of other adducts formed from A and various ligands with the CO liberated in the flash experiment were also determined.Flash photolysis studies of the iridium(I) analogue IrCl(CO)(PPh3)2 in benzene demonstrated CO photolabilization in this case as well.The back reaction of the resulting transient species IrCl(PPh3)2 with CO displayed second-order kinetics with the respective rate constant 2.7E8/M.s.These results are discussed in terms of the catalytic mechanisms involving such species.
