bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation and Characterization of Optically Active Quadridentate Schiff Base-Titanium(IV) Complexes and the Catalytic Properties of These Complexes on Asymmetric Oxidation of Methyl Phenyl Sulfide with Organic Hydroperoxides
Authors: Sasaki Caori , Nakajima Kiyohiko , Kojima Masaaki , Fujita Junnosuke 
Published: July 2006

Abstract
Titanium(IV) complexes, [TiCl(Schiff base)]2O, with quadridentate Schiff base ligands derived from optically active 1,2-diamines and salicylaldehyde were prepared by treating TiCl4 with an equimolar amount of the Schiff base ligand in wet pyridine. The complexes were characterized by their 13C NMR, absorption, and circular dichroism spectra, and conductivity measurements. The complexes in dichloromethane take a μ-oxo dinuclear structure, and in methanol the complexes break up into a mononuclear species, [Ti(OMe)(MeOH)(Schiff base)]Cl. The complexes catalyze the asymmetric oxidation of methyl phenyl sulfide into the sulfoxide with organic hydroperoxides; the highest enantiomeric excess (ee) was ca. 60%. The kinetics conform to a rate law which is first order in the concentration of each sulfide, hydroperoxide, and complex catalyst.
Formation of Acrylaldehyde by Vapor-Phase Aldol Condensation II. Phosphate Catalysts
Authors: Ai Mamoru 
Published: July 2006

Abstract
Vapor-phase aldol condensation of formaldehyde with acetaldehyde to form acrylaldehyde was studied with various oxide and phosphate catalysts using 35% formalin as the source of formaldehyde. Almost all of the tested oxides exhibited a certain activity as the catalysts. Acidic oxides, such as MoO3 and WO3 showed a relatively high selectivity to acrylaldehyde, though the activities were low. V2O5 and amphoteric oxides exhibited a much higher activity, but they promoted also the formation of CO2 and methanol. The catalytic performance was improved, to a certain extent, by combination of an acidic oxide with an amphoteric oxide. Further, the combination of phosphorus with V2O5 or an amphoteric oxide induced a large increase in the selectivity to acrylaldehyde. A good performance was obtained with the Ni–P, Mn–P, Fe–P, and V–P systems. The yield of acrylaldehyde reached 86 mol% on the AcH basis with a very slow formation of CO2 and methanol.
Spectroelectrochemistry of New Prussian Blue Films Prepared by a Cast Method
Authors: Lin Ru-Jang , Toshima Naoki 
Published: July 2006

Abstract
New Prussian Blue (PB) films were prepared by being cast from colloidal PB dispersions in an organic solvent containing cationic surfactants. The electrochromic behaviors of the cast PB films are similar to those of electrodeposited PB films. However, the cyclic voltammetries of both the PB films were quite different from each other. To make the difference clear, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and X-ray photospectroscopy (XPS) were used in measurements of these films grown on Pt and indium tin oxide electrodes. The EDX results for fresh PB films indicated that cast films contain K+ ions, suggesting a soluble-form PB, KFe[Fe(CN)6], while electrodeposited films do not, suggesting an insoluble-form PB, Fe4[Fe(CN)6]3. The transient spectral observations indicated the participation of a unique electrochemically active iron(III) site in the reductive cycles of a cast film, although the participation of a plural electrochemically active iron(III) sites was proposed for an electrodeposited film. After a repeated cyclic scan a cast PB film maintained its unique active site, while an electrodeposited film had plural sites comprising both a soluble and an insoluble form of PB.
The Conformational Changes of Poly(l-ornithine) with Organic Counter Ions in Aqueous Sodium 1-Decanesulfonate Solution
Authors: Aoyagi Makoto , Maeda Tamaki , Hayakawa Katumitu , Satake Iwao 
Published: July 2006

Abstract
The circular dichroism study was made of the coil-helix transitions of poly(l-ornithine) with 1-alkanesulfonate counter ions of the chain length from 3 to 6 in sodium 1-decanesulfonate solution. The conformational change is insensitive to the counter ion chain length and becomes appreciable even at surfactant concentrations as low as (1–2)×10−4 mol dm−3.
Electrochemical Halogenation of Trisubstituted Germanes and Silanes
Authors: Okano Mitsutoshi , Mochida Kunio 
Published: July 2006

Abstract
Electrochemical halogenation of trisubstituted germanes and silanes in acetonitrile occurred in the cathode compartment in contrast to the well-known electrochemical halogenations which always occur in the anode compartment.
Photolysis of Thietane and Thietane-d6 in Argon Matrix: Infrared Spectra of Matrix-Isolated Thioformaldehyde and Thioformaldehyde-d2
Authors: Watanabe Osamu , Suzuki Eiichi , Watari Fumio 
Published: July 2006

Abstract
Argon-matrix isolated thietane at 10 K decomposed by irradiation (λ&gt;290 nm) to form ethylene and thioformaldehyde. The photolysis of thietane under these conditions has been shown to be a clean source of thioformaldehyde. The CH2S and CD2S molecules generated this way are indefinitely stable and their infrared spectra could be recorded.
Synthesis of Ti-Containing Pillared Montmorillonite Using a Trinuclear Acetatochlorohydroxo Titanium(III) Complex
Authors: Kijima Tsuyoshi , Nakazawa Hiromoto , Takenouchi Satoshi 
Published: July 2006

Abstract
Trinuclear acetato-chloro-hydroxo titanium(III) chloride, [TiIII3(OCOCH3)6.4Cl1.2(OH)0.4]Cl·11H2O, was prepared; its aqueous solution was reacted with Ca- and Cu-montmorillonites in air. Titanium(III) complex ions were mostly hydrolyzed, oxidized and condensed into their polynuclear forms, replacing the interlayer metal ions of montmorillonite. The calcined forms of both reaction products maintain large interlayer spacings of 22.2 and 21.3 Å, and have specific surface areas of 105 and 128 m2 g−1, respectively.
Syntheses and Characterization of 2,4-Dioxo-3,3-pentanediselenolato Platinum(II) Complex and Its Dithiolato Analog Prepared by Se–C and S–C Bond Cleavages of 2,3-Diseleno-1,1,4,4-tetraacetylbutane and 2,3-Dithio-1,1,4,4-tetraacetylbutane
Authors: Yamazaki Shinsaku , Ueno Tamio , Hojo Masashi 
Published: July 2006

Abstract
2,4-Dioxo-3,3-Pentanediselenolato(Se2-ac) platinum(II) complex [Pt(Se2-ac)(PMe2Ph)2] and its dithiolato analog [Pt(S2-ac)(PMe2Ph)2] have been prepared by treating cis-[PtCl2(PMe2Ph)2] with 2,3-diseleno-1,1,4,4,-tetraacetylbutane and 2,3-dithio-1,1,4,4-tetraacetylbutane in a KOH/acetone–methanol mixed solution. The IR, 1H, 13C, and 31P NMR and mass spectra of these complexes are discussed.
Halogenative Allylation and Reduction of Aromatic Acetals by Double Substitution of Alkoxyl Groups in Acetal
Authors: Oriyama Takeshi , Iwanami Katsuyuki , Tsukamoto Kazuhisa , Ichimura Yuichi , Koga Gen 
Published: July 2006

Abstract
In the presence of excessive amount of acetyl halide along with a catalytic amount of tin(II) halide, aromatic acetals react with allyltrimethylsilane or triethylsilane to give α-allylbenzyl halides or benzyl halides, respectively, in good to excellent yields.
A Convenient Synthesis of 4-(Phenylsulfonylthio)-2-azetidinones
Authors: Tanaka Hideo , Taniguchi Masatoshi , Uto Seiryu , Shiroi Takashi , Sasaoka Michio , Torii Sigeru 
Published: July 2006

Abstract
4-(Phenylsulfonylthio)-2-azetidinones have been prepared conveniently by the reaction of 4-(2-benzothiazolyldithio)-2-azetidinones with 2-benzothiazolyl benzenethiosulfonates. A combination of this reaction with the electrolytic cross-coupling of bis(benzothiazolyl) disulfide and ammonium benzenesulfinate can establish a recycling system, in which S-(2-benzothiazolyl) benzenethiosulfonate is regenerated to play a critical role in penicillin–cephalosporin conversions.
Reactions of 1,1-Diphenyl-2-methylpropene Cation Radicals with Methanol. Ketone Formation Involving Carbocation Rearrangement
Authors: Akaba Ryoichi , Aihara Shin , Sakuragi Hirochika , Tokumaru Katsumi 
Published: July 2006

Abstract
Anodic oxidation of 1,1-diphenyl-2-methylpropene (1) in an acetonitrile–methanol mixture under argon gave 3,3-diphenyl-2-butanone (2) in high yield together with small amounts of 1,2-diphenyl-2-methyl-1-propanone (3) and benzophenone (4). Similar anodic oxidation of 1 in the presence of oxygen was also carried out, and the mechanisms for the novel ketone forming reactions are discussed.
Studies on Some Dithiocarbamato-Bridged Heterobimetallic Complexes: Part II
Authors: Singh N K , Kaw Chetna , Singh Nanhai 
Published: July 2006

Abstract
Some dithiocarbamato-bridged heterobimetallic complexes of the type MI[Zn(dtc)3] and MII[Zn(dtc)3]2, (M=Co(II), Ni(II), Cu(II), Pd(II), Pb(II), Cd(II), Tl(I), Ag(I), dtc=diethyldithiocarbamate), have been synthesized and characterized by elemental analysis, molar conductance, magnetic susceptibility, (1H, 13C) NMR, UV-visible, and infrared spectral studies. The complexes are nonelectrolytes. The infrared spectral bands and NMR signals indicate the presence of only one type of dithiocarbamate group. The electronic spectra of the complexes recorded in chloroform, pyridine, and dimethyl sulfoxide are similar to their nujol mull spectra indicating no change in the geometry of the central metal. Magnetic moment, electronic spectra, and ESR studies are commensurate with a square-planar geometry around Co(II), Ni(II), Pd(II), and Cu(II).
Physical Characteristic and Molecular Structure of Spin-Crossover Iron(III) Complexes of Monoclinic Form with Hexadentate Ligands Derived from Triethylenetetramine and Salicylaldehyde [Fe(sal2trien)]BPli4·acetone
Authors: Maeda Yonezo , Oshio Hiroki , Tanigawa Yuichi , Oniki Takayuki , Takashima Yoshimasa 
Published: July 2006

Abstract
Iron(III) complexes of [FeL]BPh4·acetone containing the hexadentate ligand derived from triethylenetetramine and salicylaldehyde have been synthesized. These complexes were grown in two crystalline forms, monoclinic and the twin crystals. The crystal structure of the monoclinic form was determined at 290 K, at which temperature the complex is in a transition spin-state between high- and low-spin states; the spin-state interconversion rate of the monoclinic form is as fast as the inverse of the Mössbauer lifetime (1×10−7s) above 200 K. The monoclinic crystal of [FeL]BPh4·acetone is of space group P21⁄a, with a=27.418(4), b=10.097(2), c=14.726(3) Å, β=98.00(1)°C, and Z=4. The average bond distances of Fe–O (1.875 Å), Fe–Nimine (1.988 Å), and Fe–Namine (2.069 Å) are in good agreement with the expected values for the transition spin-state between high- and low-spin states. Twin crystals are in a high-spin state over the temperature range 78–320 K.
Structure of Cobalt(II) Ion and Tri- and Tetrachlorocobaltate(II) Complexes in N,N-Dimethylformamide Determined by the Fluorescent EXAFS Method
Authors: Ozutsumi Kazuhiko , Tohji Kazuyuki , Udagawa Yasuo , Ishiguro Shin-ichi 
Published: July 2006

Abstract
EXAFS (extended X-ray absorption fine structure) spectra were measured for N,N-dimethylformamide (DMF) solutions containing cobalt(II) ion and its chloro complexes of low concentration (20–40 mmol dm−3) by a laboratory EXAFS spectrometer modified for the fluorescence detection. The analysis of the EXAFS data for a cobalt(II) perchlorate DMF solution showed that cobalt(II) ion in DMF has an octahedral structure with six DMF molecules. The Co-O (DMF) bond length within [Co(dmf)6]2+ in DMF is 206(1) pm and is practically the same as that within [Co(H2O)6]2+ (208 pm) in water within experimental uncertainties. It was also shown that the tri- and tetrachlorocobaltate(II) complexes in DMF have a tetrahedral structure. The Co–O and Co–Cl lengths within [CoCl3(dmf)]− in DMF are 202(1) and 227(1) pm, respectively. The Co–Cl distances within [CoCl]2− in DMF and in water are the same and 229(1) pm.
Mechanism of Cis–Trans Isomerization of Fluoranthenylethylenes on Direct Irradiation
Authors: Furuuchi Hideo , Kuriyama Yasunao , Arai Tatsuo , Sakuragi Hirochika , Tokumaru Katsumi 
Published: July 2006

Abstract
On direct irradiation 8-styrylfluoranthene (SF) and 8-(3,3-dimethyl-1-butenyl)fluoranthene (BF) underwent two-way and one-way isomerizations, respectively, in the triplet manifold after intersystem crossing of the initially produced singlet excited state.
Combustion Reactions in Methane–Air Premixed Flames
Authors: Fukutani Seishiro , Sakaguchi Keizo , Kunioshi Nílson , Jinno Hiroshi 
Published: July 2006

Abstract
A reaction scheme reproducing methane combustion by computer simulation under a wide range of stoichiometric ratio has been proposed and applied to flat methane–air premixed flames to elucidate factors determining their propagation mechanisms and the role of C2 reaction pathways. Main methane combustion reactions, which progress sequentially from the fuel to carbon dioxide, are inhibited at low temperatures due to retarded production of oxygen atoms which are necessary for the oxidation of methyl radicals. The role of C2 routes have been investigated by comparison of the results obtained by use of the C2 scheme and a simplified C1 scheme. Some of the methyl radicals are once recombined to ethane but most of the produced ethane is dissociated again to methyl via ethyl radicals. Then the C2 routes work as a temporary storage of species and hinder the main combustion reactions which go through C1 species.
Increase of Solvent-Soluble Products of Coal by Repeated Butylation with Zinc and Butyl Iodide under Mild Conditions
Authors: Yoneyama Yoshiharu , Yamamura Yutaka , Hasegawa Kiyoshi , Kato Tsutomu 
Published: July 2006

Abstract
Yubari and Taiheiyo coals were repeatedly butylated with zinc metal powder and butyl iodide under mild conditions. After the benzene-soluble products (BS) from each reaction were combined the mixture was further butylated. The BS and its butylation products (Bu.BS) were fractionated by gel permeation chromatography. At each reaction step, BS with a similar structural character but different degrees of polymerization were solubilized for Taiheiyo coal; for Yubari coal BS with similar characteristics were solubilized. A large portion of these Bu.BS from both coals were solubilized in hexane. The molecular weight of BS decreased after butylation. These results suggest that this procedure brings about depolymerization as well as the introduction of butyl groups, while enhancing solubilization.
Hydroformylation–Amidocarbonylation of Methylvinylphosphinate. Application to Synthesis of Glufosinate
Authors: Sakakura Toshiyasu , Huang Xin-Yan , Tanaka Masato 
Published: July 2006

Abstract
Glufosinate, 2-amino-4-[(hydroxy)methylphosphinyl]butanoic acid, (2a) was synthesized from 2-chloroethyl methylvinylphosphinate (1a) via successive hydroformylation–amidocarbonylation. Hydroformylation of 1a catalyzed by Co2(CO)8 in methanol gave 2-chloroethyl (3,3-dimethoxypropyl)methylphosphinate (5). Crude 5 was subjected to cobaltcatalyzed amidocarbonylation to afford N-acylglufosinic acid methyl ester (2b). Hydrolysis of 2b under acidic conditions gave 2a quantitatively.
Thermal Properties of Liquid-Crystalline Polyitaconates with Paired Mesogens
Authors: Sugiyama Kazuo , Shiraishi Kohei 
Published: July 2006

Abstract
2-Methylenesuccinates (Itaconates) (2) having two 4-methoxyazobenzene moieties as paired mesogenic groups were prepared. The monomer 2 was radically homopolymerized and copolymerized with non-mesogenic monomer, dioctadecyl itaconate (DOI). Paired mesogenic homopolyitaconate exhibits a nematic phase and the copolymers of the monomer 2 with DOI also show a mesomorphic phase up to 25 mol% of DOI content. The enhancement of mesophase formation by paired mesogens is discussed.
Formation of 1,2-Dioxanes by the Use of Tris(2,4-pentanedionato)manganese(III) or Manganese(III) Acetate
Authors: Nishino Hiroshi , Tategami Shin-ichi , Yamada Takashi , Korp James D , Kurosawa Kazu 
Published: July 2006

Abstract
The reactions of 1,1-diphenylethene, 1,1-bis(4-chlorophenyl)ethene, 1,1-bis(4-methoxyphenyl)ethene, 1,1-bis(4-methylphenyl)ethene, 1,1-bis(4-fluorophenyl)ethene, styrene, 1-octene, cyclohexene, and cyclooctene with tris(2,4-pentanedionato)manganese(III) ([Mn(acac)3]) in acetic acid at room temperature give 4-acetyl-3-methyl-1,2-dioxan-3-ol in 8–92% yields, together with 3-acetyl-4-hydroxy-3-hexene-2,5-dione. The similar reactions of 1,1-diphenylethene with 2,4-pentanedione, 3-methyl-2,4-pentanedione, 3-ethyl-2,4-pentanedione, 1-phenyl-1,3-butanedione, acetoacetanilide, and 1,3-cyclohexanedione in the presence of manganese(III) acetate also give the corresponding cyclic peroxide in good to moderate yields. The mechanisms of manganese(III)-induced 1,2-dioxane ring formation and concomitant radical side reaction are discussed.
Alkynylations of Oxiranes with Lithium Acetylides by the Catalysis of Trimethylgallium
Authors: Fukuda Yukitoshi , Matsubara Seijiro , Lambert Claude , Shiragami Hiroshi , Nanko Toshiki , Utimoto Kiitiro , Nozaki Hitosi 
Published: July 2006

Abstract
The reaction of 1-lithio-1-alkynes with oxiranes under the catalytic action of trimethylgallium afforded the corresponding β-hydroxy acetylenic compounds in good yields with excellent regioselectivities. No isomerization of oxiranes was observed during the reactions because of low Lewis acidity of trimethylgallium. The mechanism including activation of an oxirane by the coordination to trimethylgallium was proposed.
Kinetic Studies of Electron-Transfer Reactions Induced by the Reductive Quenching of Tris(2,2′-bipyrazine)ruthenium(II)
Authors: Yamazaki-Nishida Suzuko , Kimura Masaru 
Published: July 2006

Abstract
The oxidation reaction of the oxalate ion (C2O42−) by the peroxodisulfate ion (S2O82−) is greatly accelerated by irradiation with visible light in an aqueous solution containing tris(2,2′-bipyrazine)ruthenium(II) ([Ru(bpz)3]2+). The mechanism constitutes a chain reaction initiated by a reductive quenching of photoexcited [Ru(bpz)3]2+ with C2O42−. The rate of reaction increases with an increase of the [Ru(bpz)3]2+ concentration or incident light intensity. On the other hand, the reaction rate hardly depends not only on the concentrations of C2O42− and S2O82−, but also on the ionic strength and temperature. The [Ru(bpz)3]2+ acts as a photo-catalyst, although the absorption spectra of the reaction solution are slightly changed during the photoreaction. An analysis of the absorption spectra by a graphic method indicates that another absorbing species than [Ru(bpz)3]2+ is formed in the reaction solution. Such a complex has no photocatalytic effect for the redox reaction between S2O82− and C2O42−. The concentration of the produced complex is always coincident with ca. 0.7% of that of the S2O82− reacted. The reaction mechanism and rate law are clarified to account for the results obtained.
The Intercalation of n-Alkylamines into Layered Transition Metal Phosphates-Solvent Effect
Authors: Kanzaki Yasushi , Abe Mitsuo 
Published: July 2006

Abstract
The intercalation of n-alkylamines (carbon number 1–18) into γ-titanium phosphate and γ-zirconium phosphate was examined in aqueous, methanol, and benzene solutions. The interlayer spacings increased with an increase in the carbon number of alkylamines, showing the formation of bilayers of alkylamines in a similar manner to that in previous reports. The intercalation reaction depended on the solvents used to dissolve the alkylamines. For example, an anomaly was observed regarding intercalation in ethanol solutions. The interlayer spacings decreased when the carbon number exceeded 14–16, indicating a distortion or the monolayer formation of alkylamines. The rate of intercalation was also seriously affected by the kind of solvents. Intercalation occurred almost instantaneously in aqueous solutions. The rate of the intercalation reaction was generally faster in benzene solutions than that in ethanol solutions. The formation of bilayers was also more perfect in benzene solutions, and resulting interlayer spacings were slightly larger than those prepared in ethanol solutions. The anomaly in ethanol was attributed to a disturbance due to the cointercalation of methanol molecules. The solvent effect was also accountable due to the dielectric constant, or dipole moment, of solvents.
Structural Study of Optical Resolution. XVI. The Crystal Structures of a Pair of Diastereomeric Salts of the lel3-Tris(trans-1,2-cyclohexanediamine)nickel(II) Complex with d-Tartrate Dianion
Authors: Mizuta Tsutomu , Miyoshi Katsuhiko 
Published: July 2006

Abstract
The crystal structures of the diastereomeric salt pair, Λ-lel3-[Ni(S,S-chxn)3](d-tart)·3H2O (1) and Δ-lel3-[Ni(R,R-chxn)3](d-tart)·5H2O (2) (chxn=trans-1,2-cyclohexanediamine and d-tart=(+)-(R,R)-tartrate dianion), have been determined by single-crystal X-ray diffraction techniques. Crystal 1 is orthorhombic with the space group P212121, a=10.093(2), b=13.589(4), c=22.011(4) Å, and Z=4. Crystal 2 is also orthorhombic with the same space group, a=11.197(2), b=13.102(2), c=22.402(2) Å, and Z=4. In 1, the d-tart ion makes a familiar face-to-face contact with the Λ complex, in which the two alcoholic and one carboxylic O atoms of the d-tart ion are involved in the multiple hydrogen bonds to the three H–N groups on the triangular face of the complex. This contact mode resembles the one found earlier in the chloride d-tart salt of the corresponding Λ Co(III) complex, Λ-lel3-[Co(S,S-chxn)3]Cl(d-tart)·2H2O (3). On the other hand, no such face-to-face contact is present in 2, though it has been found in the corresponding Δ Co(III) complex salt, Δ-lel3-[Co(R,R-chxn)3]Cl(d-tart)·2H2O (4) in which the d-tart ion is obliged to rotate the distal carboxylato group so as to avoid the steric repulsion otherwise imposed on it by one of the bulky chxn ligands. Detailed comparison of the above four crystal structures revealed that the packing modes of the respective complex cations and counterions are surprisingly similar to one another, indicating that the absence of such a face-to-face contact in 2 is attributed to the weaker affinity of the d-tart ion for the divalent Δ Ni(II) complex, rather than to the steric demands of the crystal packing in 2. In 2 are found two deformed contact modes similar to each other, in which the d-tart ion directs its three O atoms to the triangular face, but only one of them is hydrogen-bonded to one or two of the three H–N groups on the triangular face. The d-tart ion thereby avoids the steric repulsion that would be imposed on it if it should make a usual face-to-face contact with the Δ complex.
Asymmetric Transformation of (RS)-2-Phenylglycine via Formation of Salt with (1S)-10-Camphorsulfonic Acid
Authors: Shiraiwa Tadashi , Sakata Shinji , Fujishima Keiko , Kurokawa Hidemoto 
Published: July 2006

Abstract
An asymmetric transformation of (RS)-2-phenylglycine [(RS)-Phg] was carried out via formation of a salt with (1S)-10-camphorsulfonic acid [(S)-CS] in acetic acid, propanoic acid, or butanoic acid by heating at 100 °C without using any catalysts such as aldehydes. The rate of epimerization of a more soluble salt of (S)-Phg with (S)-CS was estimated to be lowest in acetic acid and highest in butanoic acid. The asymmetric transformation in propanoic acid, however, was achieved successfully to give the salt of (R)-Phg with (S)-CS with 100% optical purity in 82% yield. Optically pure (R)-Phg was obtained from the salt in 80% yield based on the (RS)-Phg used as the starting material.
A Combined Solvent Extraction-Spectrophotometry for the Determination of Bismuth(III)
Authors: Desai Ganesh Shantilal , Shinde Vijay Malhar 
Published: July 2006

Abstract
A method has been proposed for the extraction of bismuth(III) at microgram level from bromide media using mesityl oxide as an extractant. The bismuth–bromo complex formed in the concentration range of 0.05–0.3 mol dm−3 hydrobromic acid showed quantitative extraction into mesityl oxide. Various experimental conditions such as acid concentration, mesityl oxide concentration, period of equilibration, stripping agents, and diverse ions have been studied. Bismuth ion after stripping is determined by thiourea spectrophotometrically. The method is applicable to the analysis of pharmaceutical samples, alloy samples, and synthetic mixtures.