14077-30-6Relevant academic research and scientific papers
Catalysis of substitution reactions of rhodium(III) complexes. The reaction of aquopentachlororhodate(III) ion with pyridine
Rund, John V.,Basolo, Fred,Pearson, Ralph G.
, p. 658 - 661 (1964)
The observation of Delepine that alcohol facilitates the synthesis of certain rhodium(III) complexes was investigated. For the reaction between K2[Rh(H2O)Cl5] and pyridine (py) to yield trans-[Rh(py)4Cl2]Cl, it was found that the role of the alcohol is to generate catalytic amounts of a lower oxidation state of rhodium. It is assumed that this is Rh(I), and a two-electron bridged activated complex mechanism is proposed for the catalysis reaction.
Synthesis, Crystal Structures and Spectroscopic Properties of cis- and trans-+ : Reinvestigation of the dmpe Complexes
Suzuki, Takayoshi,Isobe, Kiyoshi,Kashiwabara, Kazuo
, p. 3609 - 3616 (1995)
Two pairs of geometrical isomers, cis- and trans-+ , have been synthesized and their structures and spectroscopic properties investigated.The previous characterization of the dmpe complexes made by other workers was found to be erroneous.A convenient method of preparation and separation of the complexes into isomers has been found.The geometrical structures of the isomers have been confirmed by 1H, 13C and 31P NMR spectroscopy and by single-crystal X-ray structure determinations.The Rh-Cl bond lengths in the cis complexes are considerably longer than those in the corresponding trans isomers, and the Rh-P bonds trans to Cl in the cis isomers are relatively shorter than those of mutually trans phosphine ligands in both the cis- and trans-isomers, exhibiting a strong trans influence of the dimethylphosphino group.The 1H, 13C and 31P NMR spectra of the complexes were found to be consistent with the structures found by single-crystal X-ray analyses, and the chemical shifts (δP) and coupling constants 1J(RhP) and 2J(PP)> correspond well with the structural parameters (Rh-P bond length and P-Rh-P angle).The electronic spectra and isomerization reactions of the complexes were also determined.
Electrochemical and spectroelectrochemical investigations of [Rh(py)4Cl2]Cl in nonaqueous solvents. Generation and reactions of monomeric rhodium(II) species
Anderson,Gregory
, p. 3905 - 3909 (2008/10/08)
An electrochemical and spectroelectrochemical investigation of trans-[Rh(py)4Cl2]Cl is reported, and the electron-transfer properties of the title complex in acetonitrile, acetonitrile/pyridine, and pyridine solvent systems in the presence and absence of chloride are presented. In the absence of water and oxygen, [Rh(py)4Cl2]Cl is reduced by one electron to form either monomeric or dimeric rhodium(II) species, depending upon the solution conditions. In excess pyridine and chloride, a reversible one-electron process is found at E1/2 = -0.74 V vs SCE, and on the basis of ESR spectroscopy and electrochemical data, formation of Rh(py)4Cl2 is assigned. The effect of the presence of water on the electron-transfer mechanism will be discussed. In addition, preliminary reaction data of the reduced species with methyl iodide is also presented. From the electrochemical, spectroelectrochemical, and ESR data, a self-consistent electron-transfer mechanism for the reduction of trans-[Rh(py)4Cl2]Cl is presented.
Homogeneous catalysis of the water-gas shift reaction by rhodium complexes in aqueous substituted pyridine solutions
Pardey,Ford
, p. 247 - 263 (2008/10/08)
Described are quantitative studies of the water-gas shift reaction (WGSR) catalysis by homogeneous solutions of RhCl3 in aqueous pyridine and other substituted pyridine solutions. This system is a stable, moderately active catalyst displaying turnover frequencies for hydrogen production (TF(H2)) of about 102 moles H2 per mole Rh per day for [Rh] = 0.01 mol 1-1, P(CO) = 0.9 atm and T = 100°C with an Ea value of approximately 11.5 kcal mol-1 deg-1. The TF(H2) values were first order in P(CO) but displayed a complex dependence on [Rh].
