• Journal of the Korean Chemical Society
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• v.45 no.1
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• pp.25-30
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• 2001

A selective kinetic fluorimetric method for the determination of trace rhodium(Ⅲ), based on the catalytic effect of rhodium(Ⅲ) on the oxidation of nile blue by periodate have been studied. The effects of pH and concentrations of nile blue, sodium periodate, trioctyl phosphine oxide(TOPO) and temperature were investigated. The calibration curve for rhodium(Ⅲ) ion was linear over the range from 100 ng/mL to 0.1 ng/mL and the detection limit was 0.01 ng/mL under the optimal experimental conditions. Effects of interferences from several cations and anions for the determination of rhodium(Ⅲ) were also investigated.

• Bulletin of the Korean Chemical Society
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• v.11 no.3
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• pp.248-250
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• 1990

Dichloro and ethylenediamine rhodium(III) complexes of a flexible $N_2O_2$-type tetradentate ligand, ethylenediamine-N,N'-di- -butyric acid(eddb), have been prepared. Both s-cis- and uns-cis geometrical isomers have been yielded in the $[Rh(eddb)Cl_2]-\;and\;[Rh(eddb)(en)]^+$ complexes. Ir, pmr, and electronic absorption spectra are used to characterize the complexes obtained in this work.

• Proceedings of the Korea Crystallographic Association Conference
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• 2002.11a
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• pp.30-30
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• 2002

Heating [Cp＊Rh(η²-NO₃)(OTf) (1) and PhC≡CPh in EtOH for 3 h gave a η⁴-cyclobutadienerhodium complex, [Cp＊Rh(η⁴-C₄Ph₄)] (2). Complex 1 reacted with HC=CPh in acetone at room temperature for 3 h to give a (η⁴-cyclobutadiene)-rhodium complex, [Cp＊Rh(η⁴-C₄HPhC=CPh)] (3). Whereas, the reactions of 1 with HC=CCH₂Cl in acetone at room temperature for 3 h gave the triply halide-bridged dinuclear rhodium complex, [Cp＊Rh(μ₂-Cl)₃RhCp＊](OTf) (4). Complexes 2-4 have been structurally characterized by X-ray diffraction.

• Bulletin of the Korean Chemical Society
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• v.18 no.8
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• pp.824-827
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• 1997

Bis(ethylene)rhodium(Ⅰ) chloride dimer reacted with vinylcyclopropane to give σ,η3-allylrhodium(Ⅲ) complex 3. Complex 3 underwent C-C bond cleavage of 8-quinolinyl ethyl ketone 11, to form η3-1,3-dimethylallylrhodium(Ⅲ) complex 8, which was reductively eliminated by trimethyl phosphite to give 8-quinolinyl-1-methylbut-2-enyl ketone (10). More sterically hindered 8-quinolinyl alkyl ketones were allowed to react with complex 3 to afford corresponding alkenes as well as a mixture of complex 8 and η3-1-ethylallyl rhodium(Ⅲ) complex 19, identified as 10 and 8-quinolinyl-pent-2-enyl ketone (20) after reductive elimination. 8-Quinolinyl alkyl ketone bearing a sterically hindered alkyl group showed less reactivity for C-C bond cleavage and higher 20/10 ratio compared with those having a less sterically hindered alkyl group, such as 8-quinolinyl ethyl ketone (11).

• Bulletin of the Korean Chemical Society
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• v.26 no.2
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• pp.225-226
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• 2005

• Resources Recycling
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• v.22 no.5
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• pp.29-34
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• 2013

Solvent extraction experiments were performed to separate platinum and rhodium from mixed chloride solution by using tri 2-ethylhexyl amine (TEHA) and its mixture with TBP and LIX 63. Effects of extraction conditions on the separation of the two metals were investigated as a function of extractant concentration in the HCl concentration range from 1 to 9 M. The concentration of Pt (IV) and Rh(III) was controlled to $1{\times}10^{-3}M$ and $2{\times}10^{-4}M$, respectively. In the extraction with TEHA and its mixture, Pt was quantitatively extracted irrespective of HCl concentration, while the extraction percentage of Rh depended on the extraction condition. When the concentration of HCl in the mixed solution was low, the extraction of Rh was nil and separation of Pt and Rh was possible. Adding TBP to TEHA had little effect on the extraction of both metals, while adding LIX63 to TEHA favored the extraction of Rh.

• Journal of the Korean Chemical Society
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• v.33 no.6
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• pp.633-643
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• 1989

The R$Rh_2(ap)_4$(2,2-trans) isomer (ap = 2-anilinopyridinate), which has two anilino nitrogens and two pyridyl nitrogens bound to each rhodium ion trans to their own kind, shows activation towards the one electron reduction of dioxygen at -0.40 V vs SCE. The ESR spectrum taken at 123 K proves the formation of a $[Rh_2(ap)_4(O_2)]$ ion with oxygen axially bound to one rhodium ion and the complex is at a RhⅡ2 oxidation state. The complex will form [$Rh_2(ap)_4(O_2)(CH_3CN)]^-$ in presence of $CH_3CN/CH_2Cl_2$ mixture without breaking the Rh-$O_2^-$ bond. When oxidized at -0.25 and 0.55 V, $[Rh_2(ap)_4(O_2)]$ will undergo two one electron oxidations to form $Rh_2(ap)_4(O_2)[Rh_2(ap)_4(O_2)]^+$. Both species have an axially bound superoxide ion but the former is at $Rh^{II}Rh^{III }$and the later at $Rh^{III}_2$ oxidation states. The ESR spetra and $CH_3CN$ addition study, on the other hand, show that the later complex is better described as $[Rh_{II}Rh^{III}(ap)_4(O_2)]^+$ with the odd electron localized on rhodium ion and the complex has an axially coordinated molecular oxygen. The electrochemical and ESR studies also show that the degree of dioxygen activation is a function of electrochemical redox potential.

• Membrane Journal
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• v.13 no.3
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• pp.200-209
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• 2003

Polymer-metal complexed membranes were prepared by solvent evaporation method using ethylcellulose, platinum(II)acetylacetonate, and rhodium(III)acetylacetonate. The various composition of metal salt(0.3-4.0 wt%) were employed to obtain the optimum performance of final membrane. EC-metal complexed membranes were characterized by FTIR and scanning electron microscopy(SEM) to observe the morphology and the performance of oxygen, nitrogen, carbon dioxide, and methane gases was tested. It was shown that the metal salts enhanced the permeability of all gases without decrease of selectivity. However, it was found that Pt had more effects on the permeability of oxygen and nitrogen gases while Rh had more effects on the permeability of carbon dioxide and methane gases. EC-Pt complexed membrane(Pt 1.0 wt%) even showed the enhanced selectivity of oxygen/nitrogen(37%) due to the affinity characteristic of Pt to oxygen.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3600-3604
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• 2010

Rhodium(III)-$Cp^*$ complexes containing labile ligands, $[Cp^*RhCl_2]_2$, [$Cp^*Rh({\eta}^2-NO_3)$(OTf)], and $[Cp^*Rh(OH_2)_3](OTf)_2$, reacted with potential linking ligands [$L^1$ = (2-thiophene)-CH=N-N=CH-(2-thiophene); $L^2$ = (2-furan)-CH=N-N=CH-(2-furan)] to give two molecular compounds, [$Cp^*Rh(L^1)Cl_2$] (1) and [$Cp^*Rh({\eta}^2-NO_3)(L^1)$]$(OTf){\cdot}CH_2Cl_2$ ($2{\cdot}CH_2Cl_2$), and one 1-dimensioanl coordination polymer, $\{[Rh(L^2)]{\cdot}(OTf)}_{\infty}$ (3). Whereas one imine nitrogen atom within the ligand is coordinated to the Rh metal in compounds 1 and 2, both nitrogen atoms are bound to two neighboring Rh metals in compound 3 to lead to a 1-D chain polymer.

• Proceedings of the Korea Crystallographic Association Conference
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• 2002.11a
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• pp.27-27
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• 2002

[Cp＊Rh(H₂O)₃](OTf)₂ (1) reacts with a stoichiometric amount of A and B [ A = Me₃SiN₃, B = 4,4'-bipridyl, (2a), A = Me₃SiNCO, B = 4,4'-bipridyl (2b)] in acetone at room temperature for 3 h to give the supramolecular complexes [Cp＊₄Rh₄(μ-A)₄(μ-B)₂] [A = Me₃SiN₃, B = 4,4'-bipridyl, (2a), A = Me₃SiNCO, B = 4,4'-bipridyl (2b)]. Complexes 2a and 2b have been structurally characterized by X-ray diffraction.